I tested this with Firefox 2.0.0.13. Firefox displays the same problem: it is not possible to open a URL in a specified running Firefox process.
This is not an Iceweasel specific bug! #411505, which described the same problem, was merged with other bugs assuming that #408883 had solved this problem, too. It hasn't. I reported this Firefox problem on bugzilla: https://bugzilla.mozilla.org/show_bug.cgi?id=427206 -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]