priority of input tags in a form

Describe in 3 steps or more how to reproduce this bug

1. go to the URL : http://onpk.net/opera/bugs/priority-with-submit-input.php
2. type some text in the field
3. press the Enter key

What do you expect to happen?

on submitting, the input-submit tag named "return" should contain the value "input submit-first" (the behaviour in Opera 8.5)

What actually happens?

on submitting, the input-submit tag named "return" contains the value "input submit-before"