Fix for two errors, that only appear under IE 8

Fix for two errors, that only appear under IE 8

 * The Internet-Explorer stumbles, when feeded with JavaScript-code that
   includes the leading "<!--", that is often used to deter older browsers
   from executing the code. Therefore this markup is filtered from the code
   before it is executed via jQuery.globalEval(). The trailing "//-->" does
   not have to be filtered, because it is a valid JavaScript-comment.
 * A global variable "OA_output" is defined, because IE 8 would complain
   loudly otherwise.