Unity will not start on Natty Server

Clean install of 11.04 Server, on an ACER, AMD 4400+, 2GB DDR2, Radeon X1200

Server didn't come with Unity, so I installed it.
A number of errors resulted. From research, I was able to resolve all errors but one.

When I try to start Unity, this is the output;
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
unity-panel-service: no process found
compiz (core) - Fatal: Couldn't open display :0
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

I should add, that I added a line to /etc/environment --
DISPLAY=:0

to prevent a warning that the variable wasn't set.

Additionally, I've run "lshw -C display" and the output was:
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
 *-display
     description: VGA compatible controller
     product: RS690 [Radeon X1200 Series]
     vendor: ATI Technologies Inc
     physical id: 5
     bus info: pci@0000:01:05.0
     version: 00
     width: 64 bits
     clock: 33MHz
     capabilities: pm msi vga_controller bus_master cap_list rom
     configuration: driver=radeon latency=64
     resources: irq:18 memory:d0000000-dfffffff memory:fdef0000-fdefffff ioport:de00(size=256) memory:fdd00000-fddfffff
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

I've looked all over the forums, and I'm not seeing anything about this problem. I'd appreciate any help you can offer!