Problems with GIMP

[gundo]

I have tried to use the portable application GIMP from the web, but It doesnt seems to work properly. I can only open xcf files, if I try to open another type of files, like jpeg, an error window opens saying "Unknown file type".
I have tried to package the application getting the same error.
Distributions testeds are ubuntu 10.04 and ubuntu 11.04
¿Is gimp working in another distributions?

[probono]

Please run it from the command line and watch for erros, especially when you perform the actions that don't work. Probably a library isn't loaded properly?