A blank line is used to separate the header from the content in an HTTP response. Therefore simply move the blank return to the end of the header, instead of embedded in the Content-type print statment: 
print "Content-type: image/gif\n";
print "Cache-control: no-cache\n";
print "Pragma: no-cache\n";
print "Expires: Mon, 06 May 1996 04:57:00 GMT\n";
print "\n"; # End Header

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- Miller

In reply to Re: Preventing Web Client From Caching by wind
in thread Preventing Web Client From Caching by Anonymous Monk

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