AVR-Chat

I'm using the IAR compiler V5.11 or 5.12 and need to use the feature  
that has the linker write a CRC in the last two bytes of the executable.

I got the linker to write the CRC and I am able to read it back.  The  
problem is, I can't manage to compute the same one.  I have tried  
several different routines to generate the CRC and they agree with  
each other, but not with what IAR computes.  In each case, it is  
supposed to be a CRC 16 of the CCITT variety with 0x1021 as the  
polynomial.

Has anyone gotten this to work?  Is there some sample code somewhere  
that has been shown to work with the IAR computed CRC?

Thanks.