At my board the version of Link14716 is working and better... HTML in signatures is now also only allowed for admins, yet that what I wanted first, thanks Link
But html code in quotes of normal users, in the signature editor preview (low priority, because only admins can't see their html-code in the preview, for users it's correcly not parsed as it should be if html is disabled and ok so) and in the Topic Review area isn't still parsed...