Strange nonconstant validation error

When I try to validate my (previously valid) website, I get a single  
error, without an error message or further explanation. The line and  
column referred to by the error message changes every time I click  
'Revalide'. This is a bit puzzling...I've never had such problems with  
the validator before, and have always managed to pinpoint the error  
after a while.

http://validator.w3.org/check?uri=http://folk.ntnu.no/hallvabo/index.php;ss=1;verbose=1

Hallvard Norheim Bø

Received on Friday, 3 August 2007 11:44:55 UTC