Can't Delete Mail Account In Leopard

She was having mail issues (passwords etc) so rather then messing with all the random settings I decided to delete the account and then re-enter it so it auto-fills everything. Only problem was that when I hit the delete button it removed the account and all the stuff from the inbox etc but then popped up a messages saying something like "are you sure you want to do this as deleting everything will be lost". Something along those lines. I wasn't sure what it was talking about so I hit cancel to stop it.

Now it seems to be gripping onto that mail account half way. I can close the email program and reopen and then account shows up again in the list of accounts. If I remove it (no messages pop up) then it disappears and about 10 seconds later I get a popup message saying that the mail accounts password is wrong? Though there is no accounts listed and I've even deleted all the passwords from keychain etc. If I enter a password it does nothing (I know I have the right password).Then, if I close mail and reopen the account is listed in the preferences again automaticly? I keep deleting it but it keeps popping back in but with no emails etc and a bunch of password etc popups bugging me. I can't seem to ADD the account again either as it just comes up with an error I think because that account is halfway in the mail app somehow.Is there anyway to manually remove any trace of this account from the mail app or something so that I can re-add it fresh?