Serial port not working in Dell optiplex 3010

I just bought Dell optiplex 3010 and installed WINDOWS7 and Ubuntu 10.4 on it.
Serial port is working fine in windows but in ubuntu it is not working.
Output of lspci is as below:
"00:00.0 Host bridge: Intel Corporation Device 0150 (rev 09)
00:02.0 VGA compatible controller: Intel Corporation Device 0152 (rev 09)
00:16.0 Communication controller: Intel Corporation Cougar Point HECI Controller #1 (rev 04)
00:1a.0 USB Controller: Intel Corporation Cougar Point USB Enhanced Host Controller #2 (rev 04)
00:1b.0 Audio device: Intel Corporation Cougar Point High Definition Audio Controller (rev 04)
00:1c.0 PCI bridge: Intel Corporation Cougar Point PCI Express Root Port 1 (rev b4)
00:1c.1 PCI bridge: Intel Corporation Cougar Point PCI Express Root Port 2 (rev b4)
00:1c.4 PCI bridge: Intel Corporation Cougar Point PCI Express Root Port 5 (rev b4)
00:1d.0 USB Controller: Intel Corporation Cougar Point USB Enhanced Host Controller #1 (rev 04)
00:1f.0 ISA bridge: Intel Corporation Device 1c5c (rev 04)
00:1f.2 SATA controller: Intel Corporation Cougar Point 6 port SATA AHCI Controller (rev 04)
00:1f.3 SMBus: Intel Corporation Cougar Point SMBus Controller (rev 04)
02:00.0 Serial controller: SUNIX Co., Ltd. Device 1999
03:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 06)
"

and Output of lshw is as below:
"ahmcpu0246
    description: Desktop Computer
    product: OptiPlex 3010
    vendor: Dell Inc.
    version: 01
    serial: 325P7X1
    width: 32 bits
    capabilities: smbios-2.7 dmi-2.7 smp-1.4 smp
    configuration: boot=normal chassis=desktop cpus=2 uuid=44454C4C-3200-1035-8050-B3C04F375831
  *-core
       description: Motherboard
       product: 042P49
       vendor: Dell Inc.
       physical id: 0
       version: A01
       serial: /325P7X1/CN7016331C09JE/
     *-firmware
          description: BIOS
          vendor: Dell Inc.
          physical id: 0
          version: A08 (12/07/2012)
          size: 64KiB
          capacity: 8128KiB
          capabilities: pci pnp upgrade shadowing cdboot bootselect socketedrom edd int13floppy1200 int13floppy720 int13floppy2880 int5printscreen int9keyboard int14serial int17printer acpi usb biosbootspecification netboot
     *-cpu:0
          description: CPU
          product: Intel(R) Core(TM) i3-3220 CPU @ 3.30GHz
          vendor: Intel Corp.
          physical id: 46
          bus info: cpu@0
          version: 6.10.9
          serial: 0003-06A9-0000-0000-0000-0000
          slot: CPU 1
          size: 1600MHz
          capacity: 3300MHz
          width: 64 bits
          clock: 100MHz
          capabilities: boot fpu fpu_exception wp vme de pse tsc msr pae mce cx8 apic mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx rdtscp x86-64 constant_tsc arch_perfmon pebs bts xtopology nonstop_tsc aperfmperf pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 popcnt xsave avx f16c lahf_lm arat tpr_shadow vnmi flexpriority ept vpid cpufreq
          configuration: id=3
        *-cache:0
             description: L1 cache
             physical id: 36
             slot: CPU Internal L1
             size: 128KiB
             capacity: 128KiB
             capabilities: internal write-through data
        *-cache:1
             description: L2 cache
             physical id: 37
             slot: CPU Internal L2
             size: 512KiB
             capacity: 512KiB
             capabilities: internal write-through unified
        *-cache:2
             description: L3 cache
             physical id: 38
             slot: CPU Internal L3
             size: 3MiB
             capacity: 3MiB
             capabilities: internal write-back unified
        *-logicalcpu:0
             description: Logical CPU
             physical id: 3.1
             width: 64 bits
             capabilities: logical
        *-logicalcpu:1
             description: Logical CPU
             physical id: 3.2
             width: 64 bits
             capabilities: logical
        *-logicalcpu:2
             description: Logical CPU
             physical id: 3.3
             width: 64 bits
             capabilities: logical
        *-logicalcpu:3
             description: Logical CPU
             physical id: 3.4
             width: 64 bits
             capabilities: logical
        *-logicalcpu:4
             description: Logical CPU
             physical id: 3.5
             width: 64 bits
             capabilities: logical
        *-logicalcpu:5
             description: Logical CPU
             physical id: 3.6
             width: 64 bits
             capabilities: logical
        *-logicalcpu:6
             description: Logical CPU
             physical id: 3.7
             width: 64 bits
             capabilities: logical
        *-logicalcpu:7
             description: Logical CPU
             physical id: 3.8
             width: 64 bits
             capabilities: logical
        *-logicalcpu:8
             description: Logical CPU
             physical id: 3.9
             width: 64 bits
             capabilities: logical
        *-logicalcpu:9
             description: Logical CPU
             physical id: 3.a
             width: 64 bits
             capabilities: logical
        *-logicalcpu:10
             description: Logical CPU
             physical id: 3.b
             width: 64 bits
             capabilities: logical
        *-logicalcpu:11
             description: Logical CPU
             physical id: 3.c
             width: 64 bits
             capabilities: logical
        *-logicalcpu:12
             description: Logical CPU
             physical id: 3.d
             width: 64 bits
             capabilities: logical
        *-logicalcpu:13
             description: Logical CPU
             physical id: 3.e
             width: 64 bits
             capabilities: logical
        *-logicalcpu:14
             description: Logical CPU
             physical id: 3.f
             width: 64 bits
             capabilities: logical
        *-logicalcpu:15
             description: Logical CPU
             physical id: 3.10
             width: 64 bits
             capabilities: logical
     *-memory
          description: System Memory
          physical id: 39
          slot: System board or motherboard
          size: 4GiB
        *-bank:0
             description: DIMM Synchronous 1333 MHz (0.8 ns)
             product: HMT351U6CFR8C-H9
             vendor: Hynix/Hyundai
             physical id: 0
             serial: 0221DB02
             slot: ChannelA-DIMM0
             size: 4GiB
             width: 64 bits
             clock: 1333MHz (0.8ns)
        *-bank:1
             description: DIMM [empty]
             product: [Empty]
             vendor: [Empty]
             physical id: 1
             serial: [Empty]
             slot: ChannelB-DIMM0
     *-cpu:1
          physical id: 1
          bus info: cpu@1
          version: 6.10.9
          serial: 0003-06A9-0000-0000-0000-0000
          size: 1600MHz
          capacity: 1600MHz
          capabilities: vmx ht cpufreq
          configuration: id=3
        *-logicalcpu:0
             description: Logical CPU
             physical id: 3.1
             capabilities: logical
        *-logicalcpu:1
             description: Logical CPU
             physical id: 3.2
             capabilities: logical
        *-logicalcpu:2
             description: Logical CPU
             physical id: 3.3
             capabilities: logical
        *-logicalcpu:3
             description: Logical CPU
             physical id: 3.4
             capabilities: logical
        *-logicalcpu:4
             description: Logical CPU
             physical id: 3.5
             capabilities: logical
        *-logicalcpu:5
             description: Logical CPU
             physical id: 3.6
             capabilities: logical
        *-logicalcpu:6
             description: Logical CPU
             physical id: 3.7
             capabilities: logical
        *-logicalcpu:7
             description: Logical CPU
             physical id: 3.8
             capabilities: logical
        *-logicalcpu:8
             description: Logical CPU
             physical id: 3.9
             capabilities: logical
        *-logicalcpu:9
             description: Logical CPU
             physical id: 3.a
             capabilities: logical
        *-logicalcpu:10
             description: Logical CPU
             physical id: 3.b
             capabilities: logical
        *-logicalcpu:11
             description: Logical CPU
             physical id: 3.c
             capabilities: logical
        *-logicalcpu:12
             description: Logical CPU
             physical id: 3.d
             capabilities: logical
        *-logicalcpu:13
             description: Logical CPU
             physical id: 3.e
             capabilities: logical
        *-logicalcpu:14
             description: Logical CPU
             physical id: 3.f
             capabilities: logical
        *-logicalcpu:15
             description: Logical CPU
             physical id: 3.10
             capabilities: logical
     *-pci
          description: Host bridge
          product: Intel Corporation
          vendor: Intel Corporation
          physical id: 100
          bus info: pci@0000:00:00.0
          version: 09
          width: 32 bits
          clock: 33MHz
        *-display UNCLAIMED
             description: VGA compatible controller
             product: Intel Corporation
             vendor: Intel Corporation
             physical id: 2
             bus info: pci@0000:00:02.0
             version: 09
             width: 64 bits
             clock: 33MHz
             capabilities: msi pm bus_master cap_list
             configuration: latency=0
             resources: memory:f7800000-f7bfffff memory:e0000000-efffffff(prefetchable) ioport:f000(size=64)
        *-communication UNCLAIMED
             description: Communication controller
             product: Cougar Point HECI Controller #1
             vendor: Intel Corporation
             physical id: 16
             bus info: pci@0000:00:16.0
             version: 04
             width: 64 bits
             clock: 33MHz
             capabilities: pm msi bus_master cap_list
             configuration: latency=0
             resources: memory:f7c0a000-f7c0a00f
        *-usb:0
             description: USB Controller
             product: Cougar Point USB Enhanced Host Controller #2
             vendor: Intel Corporation
             physical id: 1a
             bus info: pci@0000:00:1a.0
             version: 04
             width: 32 bits
             clock: 33MHz
             capabilities: pm debug bus_master cap_list
             configuration: driver=ehci_hcd latency=0
             resources: irq:16 memory:f7c08000-f7c083ff
        *-multimedia
             description: Audio device
             product: Cougar Point High Definition Audio Controller
             vendor: Intel Corporation
             physical id: 1b
             bus info: pci@0000:00:1b.0
             version: 04
             width: 64 bits
             clock: 33MHz
             capabilities: pm msi pciexpress bus_master cap_list
             configuration: driver=HDA Intel latency=0
             resources: irq:22 memory:f7c00000-f7c03fff
        *-pci:0
             description: PCI bridge
             product: Cougar Point PCI Express Root Port 1
             vendor: Intel Corporation
             physical id: 1c
             bus info: pci@0000:00:1c.0
             version: b4
             width: 32 bits
             clock: 33MHz
             capabilities: pci pciexpress msi pm bus_master cap_list
             configuration: driver=pcieport
             resources: irq:24
        *-pci:1
             description: PCI bridge
             product: Cougar Point PCI Express Root Port 2
             vendor: Intel Corporation
             physical id: 1c.1
             bus info: pci@0000:00:1c.1
             version: b4
             width: 32 bits
             clock: 33MHz
             capabilities: pci pciexpress msi pm bus_master cap_list
             configuration: driver=pcieport
             resources: irq:25 ioport:e000(size=4096)
           *-communication UNCLAIMED
                description: Serial controller
                product: SUNIX Co., Ltd.
                vendor: SUNIX Co., Ltd.
                physical id: 0
                bus info: pci@0000:02:00.0
                version: 00
                width: 32 bits
                clock: 33MHz
                capabilities: pm msi pciexpress cap_list
                configuration: latency=0
                resources: ioport:e020(size=32) ioport:e000(size=32)
        *-pci:2
             description: PCI bridge
             product: Cougar Point PCI Express Root Port 5
             vendor: Intel Corporation
             physical id: 1c.4
             bus info: pci@0000:00:1c.4
             version: b4
             width: 32 bits
             clock: 33MHz
             capabilities: pci pciexpress msi pm bus_master cap_list
             configuration: driver=pcieport
             resources: irq:26 ioport:d000(size=4096) ioport:f0000000(size=1048576)
           *-network
                description: Ethernet interface
                product: RTL8111/8168B PCI Express Gigabit Ethernet controller
                vendor: Realtek Semiconductor Co., Ltd.
                physical id: 0
                bus info: pci@0000:03:00.0
                logical name: eth0
                version: 06
                serial: a4:1f:72:5e:8c:83
                size: 1GB/s
                capacity: 1GB/s
                width: 64 bits
                clock: 33MHz
                capabilities: pm msi pciexpress msix vpd bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation
                configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=full ip=10.99.14.131 latency=0 link=yes multicast=yes port=MII speed=1GB/s
                resources: irq:28 ioport:d000(size=256) memory:f0004000-f0004fff(prefetchable) memory:f0000000-f0003fff(prefetchable)
        *-usb:1
             description: USB Controller
             product: Cougar Point USB Enhanced Host Controller #1
             vendor: Intel Corporation
             physical id: 1d
             bus info: pci@0000:00:1d.0
             version: 04
             width: 32 bits
             clock: 33MHz
             capabilities: pm debug bus_master cap_list
             configuration: driver=ehci_hcd latency=0
             resources: irq:23 memory:f7c07000-f7c073ff
        *-isa
             description: ISA bridge
             product: Intel Corporation
             vendor: Intel Corporation
             physical id: 1f
             bus info: pci@0000:00:1f.0
             version: 04
             width: 32 bits
             clock: 33MHz
             capabilities: isa bus_master cap_list
             configuration: latency=0
        *-storage
             description: SATA controller
             product: Cougar Point 6 port SATA AHCI Controller
             vendor: Intel Corporation
             physical id: 1f.2
             bus info: pci@0000:00:1f.2
             logical name: scsi0
             version: 04
             width: 32 bits
             clock: 66MHz
             capabilities: storage msi pm bus_master cap_list emulated
             configuration: driver=ahci latency=0
             resources: irq:27 ioport:f0b0(size=8) ioport:f0a0(size=4) ioport:f090(size=8) ioport:f080(size=4) ioport:f060(size=32) memory:f7c06000-f7c067ff
           *-disk
                description: ATA Disk
                product: ST500DM002-1BD14
                vendor: Seagate
                physical id: 0.0.0
                bus info: scsi@0:0.0.0
                logical name: /dev/sda
                version: KC45
                serial: W2AQPQW1
                size: 465GiB (500GB)
                capabilities: partitioned partitioned:dos
                configuration: ansiversion=5 signature=8d7e1a0d
              *-volume:0
                   description: Windows NTFS volume
                   physical id: 1
                   bus info: scsi@0:0.0.0,1
                   logical name: /dev/sda1
                   logical name: /media/B8A23680A2364364
                   version: 3.1
                   serial: 72437ca0-c7be-3141-b121-29d58ad5f866
                   size: 100GiB
                   capacity: 100GiB
                   capabilities: primary bootable ntfs initialized
                   configuration: clustersize=4096 created=2013-03-15 08:15:52 filesystem=ntfs mount.fstype=fuseblk mount.options=rw,nosuid,nodev,relatime,user_id=0,group_id=0,default_permissions,allow_other,blksize=4096 state=mounted
              *-volume:1
                   description: Windows NTFS volume
                   physical id: 2
                   bus info: scsi@0:0.0.0,2
                   logical name: /dev/sda2
                   logical name: /media/New Volume
                   version: 3.1
                   serial: 32ca1586-f078-ad4b-a042-2d40415319e9
                   size: 165GiB
                   capacity: 166GiB
                   capabilities: primary ntfs initialized
                   configuration: clustersize=4096 created=2013-03-21 17:41:57 filesystem=ntfs label=New Volume mount.fstype=fuseblk mount.options=rw,nosuid,nodev,relatime,user_id=0,group_id=0,default_permissions,allow_other,blksize=4096 state=mounted
              *-volume:2
                   description: EXT4 volume
                   vendor: Linux
                   physical id: 3
                   bus info: scsi@0:0.0.0,3
                   logical name: /dev/sda3
                   logical name: /
                   version: 1.0
                   serial: 8343c103-850d-4312-a7d9-1df77267b783
                   size: 23GiB
                   capacity: 23GiB
                   capabilities: primary journaled extended_attributes large_files huge_files dir_nlink recover extents ext4 ext2 initialized
                   configuration: created=2013-03-21 23:30:01 filesystem=ext4 lastmountpoint=/�s�~���88���<��t�*� ���/�h�*�.>!�HM��HM�����о*�*�M� modified=2013-03-22 16:50:12 mount.fstype=ext4 mount.options=rw,relatime,errors=remount-ro,barrier=1,data=ordered mounted=2013-03-29 12:15:57 state=mounted
              *-volume:3
                   description: Extended partition
                   physical id: 4
                   bus info: scsi@0:0.0.0,4
                   logical name: /dev/sda4
                   size: 176GiB
                   capacity: 176GiB
                   capabilities: primary extended partitioned partitioned:extended
                 *-logicalvolume:0
                      description: Linux swap / Solaris partition
                      physical id: 5
                      logical name: /dev/sda5
                      capacity: 7628MiB
                      capabilities: nofs
                 *-logicalvolume:1
                      description: Linux filesystem partition
                      physical id: 6
                      logical name: /dev/sda6
                      logical name: /home
                      capacity: 168GiB
                      configuration: mount.fstype=ext4 mount.options=rw,relatime,barrier=1,data=ordered state=mounted
        *-serial UNCLAIMED
             description: SMBus
             product: Cougar Point SMBus Controller
             vendor: Intel Corporation
             physical id: 1f.3
             bus info: pci@0000:00:1f.3
             version: 04
             width: 64 bits
             clock: 33MHz
             configuration: latency=0
             resources: memory:f7c05000-f7c050ff ioport:f040(size=32)
"

what should I do now