Run this under IIS and see what happens:

#!C:\perl\bin\perl.exe
print <<EEK;
Status: 302 Moved
Set-Cookie: id=something; path=/; expires=Fri, 29-Dec-2000 21:59:38 GM
+T
Date: Fri, 22 Dec 2000 21:59:38 GMT
Location: productCategory.cgi

EEK
[download]

and see what happens. That should boil down that it is IIS, now try changing the order of the headers, specifically, move Status: to last or just before Location:

I vaguely remember this sort of thing with IIS. I recall it being sensitve to header order. Maybe I'm just insane tho. =)

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