USB automount not working but fdisk -l shows device

Hello All,
Automount of USB devices seems not to work on my fresh installed Ubuntu 10.04 on my Thinkpad T43.
The same devices are working on my older Thinkpad T23 which I just upgraded from 9.04 --> 9.10 --> 10.04.

Also the devices (USB sticks and MP3 player / Ipod) are showing up under 'lsusb' and 'blkid', 'fdisk -l' (see details below). They are just not auto-mounted and thus don't appear on the desktop as I would expect. Also this is how it works on my other PC and laptop with Ubuntu 9.04 and 10.04 without any intervention.

I greatly appreciate any help or hints !

Thanks in advance !
 -- Joerg

Here the detailed outputs:
root@erde-tp43:~# lsusb
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 002: ID 0483:2016 SGS Thomson Microelectronics Fingerprint Reader
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 003: ID 054c:0243 Sony Corp. MicroVault Flash Drive
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

root@erde-tp43:~# blkid
/dev/sda1: UUID="8170587e-90e4-445e-bf4b-d10f8b857353" TYPE="ext4"
/dev/sda5: UUID="ceb36004-2554-4a63-b3d5-7dba0b7ad8d4" TYPE="swap"
/dev/sdb1: SEC_TYPE="msdos" UUID="F263-48E2" TYPE="vfat"

root@erde-tp43:~# fdisk -l

Platte /dev/sda: 80.0 GByte, 80026361856 Byte
255 Köpfe, 63 Sektoren/Spur, 9729 Zylinder
Einheiten = Zylinder von 16065 × 512 = 8225280 Bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x0007dfeb

   Gerät boot. Anfang Ende Blöcke Id System
/dev/sda1 * 1 9328 74920960 83 Linux
/dev/sda2 9328 9730 3227649 5 Erweiterte
/dev/sda5 9328 9730 3227648 82 Linux Swap / Solaris

Platte /dev/sdb: 2013 MByte, 2013265920 Byte
129 Köpfe, 32 Sektoren/Spur, 952 Zylinder
Einheiten = Zylinder von 4128 × 512 = 2113536 Bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xc3072e18

   Gerät boot. Anfang Ende Blöcke Id System
/dev/sdb1 * 1 953 1966064 6 FAT16
Partition 1 hat unterschiedliche phys./log. Enden:
     phys=(960, 128, 32) logisch=(952, 71, 32)

* also the UDEV device system seems to work ok:
$ ls -al /dev/disk/by-uuid/
 -- shows my attached USB devices

* automount is enabled as well under gconf-edit : /apps/nautilus/preferences/media_automount