davejohn, yeah, I tried Firefox, Safari, Explorer, etc. Did not work
tonia - I tried all possible combinations: both our names, my name, his name, even his first name as last name (that often happens) - nothing works. I registered myself but not him. I did call "Automated support system" and the guy there told me that their advanced registration system was down, and when I said I had the same troubles last December and this may he could only say "I am sorry". Oh well, I mailed the registration forms today.
Thanks for all suggestions!