I think the problem is that you seem to have the x64 version of Ubuntu.
I have installed Glest successfully on Dapper (32 bit) and on Edgy (32 bit) but found that it doesn't work on Edgy 64 bit (because of reliance on 32 bit libraries).
It's a real pity because virtually everything else I need on my PC works on Edgy 64 bit, but I also need Glest so I have to keep a 32 bit OS available via multiboot.