Yes, Rob it was the image causing the problem although I'm still not clear why as the image did get returned if the cookie was set. But I swiped the following subroutine code to print the image and now the program works fine. Thanks.

my $image = 'logo.gif'; 
open(IMAGE, "<$image") or die "cannot open image file: $!"; 
my $no_bytes = (stat ($image))[7]; 
print "Content-type: image/gif\n"; 
print "Content-length: $no_bytes\n"; 
print "Pragma: no-cache\n\n"; 
print <IMAGE>; 
close(IMAGE) or die "cannot close image file: $!";
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