[ve][64] document.writeln does not allow write <br /> in document

validating http://koti.mbnet.fi/laurinps/scripts/allaboutyou.htm error [64]:
"document type does not allow element x here"

What is the main problem in here? I really have thought what is wrong, but I
didn't find out? There is just a <p>-tag and there a writing
writeln()-method, that doesn't support writing <br />?!
Is that a bug or something, that I just cannot understand?