This is the certificate authority certificate I use to sign certificates for other services I offer, like HTTP, POP3, and IMAP over SSL. If you trust this certificate then you don't have to individually trust those certificates, and you'll automatically trust certificates I issue in the future.
You should be able to install it just by clicking on the link above. Check the fingerprint to make sure it matches one of these.
SHA256 Fingerprint=3A:AA:E4:5E:D3:64:10:10:5E:73:39:EA:18:37:22:F0:F9:60:FD:53:B8:70:B1:AE:CC:91:D2:96:6F:0F:A2:1A SHA1 Fingerprint=8B:0E:B7:48:FE:10:7A:BD:53:5E:AD:BB:52:06:A6:5F:E0:11:12:4B MD5 Fingerprint=F9:BB:EC:B2:1E:6E:43:0D:50:69:31:89:17:BB:FC:13
Or check this detached signature with my public key.
This certificate was changed on May 14, 2008 in response to DSA-1571, a security advisory about weak keys in Debian discovered on May 13.
Here's a good article, which I used to make my certificate authority: Creating and Using a self signed SSL Certificates in debian.