Here are two ideas:
[1] Make sure your Pages document is saved and closed before e-mailing or compressing it;
[2] Some ISPs (like my work e-mail address) strip out .ZIP files as potential malware (it's stupid, I know). Try renaming the file with another extension like".PIZ" -- then inform your recipient to rename it back to ".ZIP."
I hope your problem is something simple like this!
Best wishes,
Clint
Problems with Pages