When you put a Radio button inside a repeat control in XPages and give it a group name as follows,
we explicitly assume that the radio buttons that get created as a result of the repeat control share the same group name and behave in a the expected way. Ofcourse there is nothing wrong in expecting that. But its just that we miss a few points that are associated with the way XPages render them- so much for the documentations of XPages..... X(
To my amusement the following is what I experienced
I did panic a bit too but that is hidden :)
The fix that I got from the sources over the internet was to add the Skip Container attribute to the radio button tag.
Click the radio button and choosing its All Properties menu and specifying 1 against the skip containers attribute helped me get the normal functionality in a tricky way X(.
Well probably my words are confusing... Take a look into the following image...
Hope this helps :)