Here’s a patch:

# diff -u multi_http_responsetime.orig multi_http_responsetime
--- multi_http_responsetime.orig        2010-02-01 10:13:22.000000000 +0100
+++ multi_http_responsetime     2010-02-01 10:30:23.000000000 +0100
@@ -16,6 +16,9 @@
 use Time::HiRes qw( time );
 use IO::Socket;

+$FAILED=0;
+$INFINITE=999999;
+
 # ----- config -----
 push(@url_array, "http://www.google.de");
 push(@url_array, "http://www.t-online.de");
@@ -34,7 +37,7 @@
                                        PeerPort => 80,
                                        Proto => 'tcp'
                                        );
-       return(0) unless ($sock);
+       return($FAILED) unless ($sock);
        print $sock "GET $baseurl HTTP/1.1\nHost: $vhost\nConnection: close\n\n";
        while (<$sock>) {
                $data .= $_;
@@ -63,11 +66,16 @@
                $baseurl =~ s@^\w+://.+?(/)@\1@;

                $tick1 = time();
-               geturl;
+               $retval = geturl;
                $tick2 = time();

-               $tspent = $tick2-$tick1;
-               $msecs = ($tspent * 1000);
+               if ($retval == $FAILED) {
+                       $msecs = $INFINITE;
+                       }
+               else {
+                       $tspent = $tick2-$tick1;
+                       $msecs = ($tspent * 1000);
+                       }

                printf "timespent$i.value %.3f\n", $msecs;
                }