Does not support automation or does not support expected interface
 

Hi,
I have been facing this peculiar problem....
Developed a .tlb on .Net that is used to fetch some data and have a
installer that installs this on my machine.
I use this .tlb in an Excel application and then consume the methods defined
therein.
The problem is that this works fine when .Net framework 1.1 is installed on
my machine, however, when i install framework 2.0 (concurrently) i get the
error "Does not support automation or does not support expected interface"
when i try to call some functions.
I am pretty much sure that am missing out something in the Excel front.

Any help/pointers are much appreciated

Cheers :o)