moving our company's ASP pages from VBS to Perlscript

Ah... A classic gotchya.

if ($rtype = "header ")
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should be changed to

if ($rtype eq "header ")
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instead. The '=' sign in the VB 'if' means equality test, but in Perl is an assignment. And also because you are comparing are two strings, you should use the 'eq' comparison keywords.