I've looked thru those suggestions before - they don't actually show a solution for 521635's problem, which is basically the same as mine.
I had this problem once before on XP, and it went away when I removed perl and IIS, then reinstalled everything from scratch. That doesn't seem to work on this machine.
A file with just print "Location: http://www.mitsi.com\n\n"; should print standard HTTP headers, then the Location line, then two new lines. If two blank lines come first, it won't forward the browser.

Here is what happens when viewed via telnet on port 80:

HTTP/1.0 302 Moved Temporarily
Date: Tue, 31 Jan 2006 19:17:55 GMT
Server: Microsoft-IIS/5.1

Location: http://www.mitsi.com
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Note the extra blank line between Server and Location: this is not correct, and I can't figure out what it takes to stop it.

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More info follows:
It's definately perlis.dll doing it. When I run the scripts with perl.exe %s %s, it runs okay. So somehow perlis.dll from activestate is broken. Unfortunately, this doesn't help me, I have to run in perlis.dll for performance reasons and to install soem services. If I install them with the command line perl, it breaks things.

<still making rummaging noises>
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