ZIP decompression problem

[Hasnain Mujtaba]

Hi,

I have an encrypted file which when I decrypt with GPG 1.0.7 I find that
the md5sum of the decrypted/decompressed file is different from the
md5sum of the original soruce file (the file sizes match however). 

If I encrypt the file without compression, then the GPG
decrypted/decompressed file has the same md5sum as the original file.
So, my guess is that there is a problem during decompression.
(Incidently, PGP8 decrypts and decompresses the data so that the md5sums
of the two files match.)

The compression algorithm used by the encryption tool (Cryptix OpenPGP)
is ZIP. The encryption (via Cryptix) and decryption (via GPG) are both
taking place on Linux and the original file is binary.  The keypair was
generated on PGP8. 

Is there something I'm missing regarding GPG and decompression via ZIP? 

Thanks,
Hasnain.