I'm getting the following error.

Invalid or untrusted server SSL certificate
Accepting this certificate poses potential security threats to your data.

Here are the details:
mail.isdbd.org presented a certificate that cannot be verified.

Certificate Issued To
Common Name (CN) localhost.localdomain
Organization Unit (OU) SomeOrganizationalUnit
Organization (O) SomeOrganization
Serial Number 0
Certificate Issued By
Common Name (CN) localhost.localdomain
Organization Unit (OU) SomeOrganizationalUnit
Organization (O) SomeOrganization
Certificate Validity
Issued On Fri Apr 10 10:30:30 BDT 2009
Expires On Sat Apr 10 10:30:30 BDT 2010
Certificate Fingerprints
SHA1 Fingerprint 84978A808D0524768B6773E98834455A157CC479
MD5 Fingerprint E1EB1703525F8E7BCB318B248B141FB9

Now, I'll be honest, I get this error everywhere. Chrome hates this, Firefox isn't too keen on it either. Most things don't but I can get them to accept it.

Zimbra looks very interesting, myself and a few colleagues are looking at it as a suitable program for use in our school. Is there a way to get the certificate accepted? Alternatively, how do I get our IT people to fix this issue and generate a trusted certificate (hopefully a no-money solution)?

And if it's of any help, this problem is happening on a Windows XP Pro system.

Thanks a lot in advance.

David