How should I explain this....
Perhaps try the following and you will end up with funny results.
1. Create a field of type Radio button in a Lotus Notes Form
2. Give values say "A" and "B" as list values in the second tab of the field properties box
3. Now preview it in the notes client and ensure that it is looks like a radio button with values "A" and "B". No wait you are not near to the bug yet
4.Get back to the designer and assign a default value of Number 1 to the radio button. Remember it is 1 and not "1". Hope you understand the difference between the text and the number
5. Save the form and Preview the same on the browser.
6. Voila you see a text field with Number 1 in it.....
How do you explain this...? I dont have one, so I call this a bug... dare to correct me ... come on give it a shot