Weird date appears on Email and iPhotos.

I have for a long time had an e-mail problem. The incoming time and date of e-mails I receive is correct but as soon as I hit the reply button, the date on the e-mail I reply, posted beneath my reply, to changes to June 15, 2009, as in "on such and such a time, June 15, 2009, so and so wrote..."
Recently while trying to fix this yet again I used the keychain access utility to review all my logins and passwords and remove those I no longer use. To my horror I discovered the same weird date as the "date modified" in all the passwords in my login keychain and as the "date expires" in all the certificates in the System Roots keychain. I can remove all the passwords and laboriously replace them in the login keychain but don't know what to do about the certificates in System Roots. All of them are labeled as "root certificate authority" and the show the correct expiry date when I click on them but all show the June 15, 2009 expiration date in the list as a whole. If I trash the lot will I be denied access to various internet sites they represent, some of which include my bank, but others appear to be from overseas (Turkey, Belgium, Switzerland, etc) and I have no idea what they represent or what they "authorize." Anyone out there who knows anything about "root certificate authority," maybe even an Apple tech (fond hope) who can help?

Powerbook G4, Mac OS X (10.3.x)