The bug is indeed due to icedove code base see https://developer.mozilla.org/en-US/Firefox/Releases/30/Site_Compatibility#Security .
To make the plugin work again (beside patching the rdf of the last version available in git), you also need to set network.negotiate-auth.allow-insecure-ntlm-v1 to true -- eric -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org