Stop Outlook from including apostrophes in email address

Hello! I'm using Outlook 2003 and have just recently began experiencing email failures due to Outlook surrounding email addresses with apostrophes.  Some specifics:
* When I start a new email 99% of the time I simply start typing the users address, and Outlook completes it for me. I believe that this "auto-complete" uses addresses you've recently emailed to.
* For some reason, some of the addresses in the "auto complete" list that pops up have apostrophes around the email address.  This is NOT apostrophes around the name, as in:
   'Smith,John'<johnsmith@xyz.com>, but:   'johnsmith@xyz.com'
* No, I'm not typing the apostrophes in at some point.  Searches on this topic indicate that this is a common problem in Outlook.
* If I send the email, it fails.  I receive:
Unable to deliver message to: <'johnsmith@xyz.com'>
Delivery failed for the following reason:
In mail queue too long, giving up.  Cause of failure:
  Unable to resolve MX or A records for xyz.com'
* You can not remove the apostrophe when trying to email.  If you completely retype the address, Outlook "helpfully" adds them back in anyways.
* The only kludge of a workaround is to add the recipient to the address book, then select them from the address book every time you email them (if you type their name you will still get the apostrophized (?) version.)

1) Can I get Outlook to stop adding the apostrophes? (Unfortunately, I can't figure out exactly when that happens... some addresses have them, some don't)
2) Where is that list of "recently used email addresses" (the ones that the auto-complete uses) stored?  Perhaps I could remove them there...
3) In the worst-case scenario, if I could just turn off the "helpful" auto-complete, I could type in an email address and maybe Outlook would get out of the way and actually USE THE ADDRESS THAT I TYPED IN.  

Thanks!