Desktop Environment Choose Problem on Ubuntu 10.10

[Adil ALPMAN]

Hi Everybody;

I have installed Ubuntu 10.10 to my laptop pc (not netbook) and as everybody 
knows ubuntu comes with ubuntu desktop environment, then i wanna use kde on 
the same system and i installed kubuntu-desktop package on it and when the 
installation ask me i choose gdm to desktop enviroment chooser on the 
startup (because all ubuntu forums offer me gdm and not kdm at this point) 
but when i restart my system i cant find any option to login with kde on 
gdm...

So, after that, when i search forums about that problem, they said there is 
little bit problem and its come from gdm...

Is there any option to choose kde or gnome at the begining of the graphical 
desktop?

ps : please use clear english if possible because my english's level in only 
upper intermediate, not perfect... :)

Thanks a lot...

Adil ALPMAN