Error message in classifieds: Bad Request - Request Too Long

[MiseryStreak]

I keep getting this when searching the classifieds:

Bad Request - Request Too Long

HTTP Error 400. The size of the request headers is too long.

I've only put two filters on (Postcode/Max Price) then filtered by newest adverts. Is this a known problem, am I doing something wrong? I'm using Firefox on a Mac (OS X 10.6.8).

[MattDell]

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