I have a similar problem.

I am having "Apache/2.2.3 (Win32) mod_ssl/2.2.3 OpenSSL/0.9.8d mod_perl/2.0.3-dev Perl/v5.8.8" as a web server, with PHP and MySql , on a windows 2003 SP2 server.

The problem is that during some period Apache hangs permanently and it
runs fine only on restarting Apache. Browser (IE) simply hangs at that time and continously keeps on rotating and ultimately after a long search...