Dmitri, what is the best way of clearing the DBGSESSID cookie when using IE?

There must be something wrong. I'm not sure why the cookie contains space in the first place. It's supposed to be just "-1" and this negative value would not trigger the debugger. Do you have httpwatch (or something like this) to check http traffic between browser and server?
When IDE runs a file "without debugger", it always appends DBGSESSID=-1 to the URL and it's enough to bypass any cookies that might remain.

But if I debug I dont have a problem.
Do I have to clear this first if I dont want to debug?
And How

Sorry if it was not clear from my last post. You don't have to clear the cookie.

Do you have mod_rewrite or something like this that may _CHANGE_ the URL or cookies on the fly?