Googlebot can follow this link but I am using a directory script whose search engine strips the 'http://' part away from external urls to save resources, so that the above link won't work, it becomes htt*://www.example.com/cgi-bin/axs/ax.cgi?www.externalsite.com/.
I modified the axs script so that it would auto-add 'http://' to the tracked urls.
From this:
elsif ($mode eq 'redir') {
print "HTTP/1.0 302 Moved\015\012" if ($IIS);
print "Location: $nexturl\015\012\015\012";
To this:
elsif ($mode eq 'redir') {
print "HTTP/1.0 302 Moved\015\012" if ($IIS);
print "Location: [$nexturl\015\012\015\012";...]
Would search engines like Google still be able to follow and index the link if the 'http://' part is only included within the function of the script?