How do I Install certs (.crt) for Microsoft Exchange on HTC Magic?

[androidj]

I'm trying to set up my work email on activesync Exchange on my HTC Magic (ROGERS. Android 1.5). In order to do this I need to download two certs (.crt) that were supplied by my company. When I try and download them though it gives me a secruity warning:

There are problems with the security certificate for this site. The name of the site does not match the name on the certificate.
Continue. View certificate. Cancel.

Then when I try and download it just continues to wait for a data connection. Meanwhile the icon it shows is a super Nintendo controller.(??!) I have all the server information and everything else seems to work with the activesync set-up, but at the last minute it just doesn't connect. I am assuming because the certs never proprely install.

Can anyone please help? Is there a cert installer that I can use?

Thanks.