Some debugging leads me to prototype.js (line 1264) but that does not make any sense to me. I have tried everything I can think of, but without any success. I do not get the error when I run Wordpress on my laptop using Apache, just when I have it running on Dreamhost which makes me suspect some security setting. I am using PHP 5.2.2 and the extra security for the domain is disabled.
Is this something anybody has bumped into? Any ideas of what to try to fix this?