Cannot set php session vars w/ Win2000pro/IIS 5

I'm running Windows 2000 pro SP4, IIS and PHP 4.3.4 . I cannot set php session variables with my current config, even though the same scripts work fine with Linux/Unix and Apache. This has been a known bug for a while with IIS and PHP, but has anyone discovered a solution?

I've tried $_SESSION['test'] = 'foobar'

and

global $test
$test = 'foobar';
session_register("test");

Nothing works! The variables do not have global scope. I can see the session files being written to the seesion data dir, but the vars don't get set. I've toggled register globals in php.ini, experimented with different session settings, double-checked permissions on the sessiondata directory, changed the session directory, tried using ISAPI, etc..

I don't use PHP with IIS and can't help you out, sorry.

Having trouble with sessions and cookies in iis 5, got the latest version of php. seems to write 2 session files, and uses the inactive one, works fine on apache. Any ideas anyone?

When that happened to me, the problem was the client browser (Internet Explorer) and its stupid security settings.
It seems that IE (since some security fix) does NOT allow cookies from websites which names are NOT alphanumeric but contain other characters too. My site's server name had and '_' in it. When I changed that the problem was gone!