they bounced back to you?
it doesn't mean they came from your machine. if another person with your address in their list is infected, those types of viruses will often spoof the email address of a random contact into the 'from' field.
that's probably what happened, though i must say i have never heard of the email bouncing back to the spoofed sender. i suppose it could happen.
if nav says you are clean you can be 99% sure you are unless you are just that lucky and got some brand new virus that nav doesn't protect against or scan for yet.
member #3240 top gun .357sig club