I’'m the guy who had the e-mailproblem when trying to register :). It looked like the validation of my e-mail address ‘‘info AT oosterlaar-online DOT nl’’ failed. I entered my secondary e-mail address ‘‘jhboosterlaar AT hotmail DOT com’’ and registration succeeded. The next thing I did, was going to the preferences page to alter my e-mail address (since I prefer my primary address). I entered the ‘‘info AT oosterlaar-online DOT nl’’ address and my settings were updated correctly. Including my e-mail address, that had been denied by the registerform.
Maybe there is some error in the validation of the registrationform? I assume that it has something to do with the dash, since it is the only special character that doesn’'t appear in my secondary e-mail address.