Booleans

Hi,
I want to maintain a boolean. I have tried several options, but none of them seem to work properly.
Option 1: Checkbox. However that does not work on update since it sets the field to On.
Option 2: Radio button. Values 0 and 1. This works in Add mode, but not in Edit mode: it does not select the radio button. This is because it compairs "Y" with the value I have in the database : 1.
Option 2: Radio button. Values Y and N. This dowsn't work at all.
Hope this makes sense.
What to do?
Thanks for your help.
Joost