i have the same problem with my installation v1.5.1.
I tell that problem my provider and he answer me that the LimitRequestLine on the apache has 8190 and that this are normaly enought…
what could i do??
EDIT: I think i have the problem/ mistake found shame.
I copy the tracking code in a separat file counter.js and include this one in my php File… now i copy the code direct to the php File and NOW it works :))