FileField and Content Profile

This bug occurs in the following setting:
* CCK (module) ver 6.x-2.2
* Content Profile (module) ver 6.x-1.x-dev
* User registration form has a file field (optional field)

On user registration page:
* If user selects a file but doesn't press the "upload" button next to the file input field -- instead submits the form by pressing the "Create Account" button; the file doesn't get uploaded.
Expected Behavior: It should upload the file whether user explicitly presses the "upload" file button or not.

* This behavior doesn't occur when editing / updating the user profile.

Thanks.