Index: sites/all/modules/ad/adserve.php
===================================================================
--- sites/all/modules/ad/adserve.php    (revision 44)
+++ sites/all/modules/ad/adserve.php    (working copy)
@@ -152,7 +152,12 @@
   if (!adserve_variable('debug')) {
     header("Content-Type: application/x-javascript; charset=utf-8");
   }
-  print "document.write('$output');";
+  
+  $output = preg_replace("/'/","\\'",$output); //escape single quotes.
+  $lines = preg_split('/(\r\n|\r|\n)/',$output); //print one line at a time.
+  foreach($lines as $l) {
+    print "document.write('$l\\n');\n";
+  }
   /**
    * TODO:
    * At some point we probably don't want to display errors to the screen, as