Hi Pragneshsp,
I've tried to repro this without luck. I've installed GAX Feb08 on a XP box with both, VS2005 and VS2008 installed, then I installed GAT for VS2005 and GAT for VS2008. I could still see the default item templates for C# and VB when creating for example a Class Library project.
If you could provide more info on what you did and confirm if what you're missing are the items I described above, that could help the guessing game.
thanks,
-Victor.