Hi and sorry for the late answer.
First of all, I suppose you are running "Category mode"
see illustration? I believe that is the only mode supported in Outlook 2003 but it's a long times since I've checked.
You need not only check which account you are synchronizing to, but also which folder. Then don't forget to select the correct folder in GMail Tasks, if that is the client you are using in the other end.
Let me know if this doesn't help you and please get back with as much details as possible
Are you
Kind Regards,
Frode Nilsen
Nilsen Labs