Old signature will not go away

Last Issue before I can upgrade to 6. The signature module is no longer, so I am using signature for forums . That seems to be working well. I had deleted the old signature module, and installed the newer signature for forums, set a new signature under the edittab of account. All good so far. All user signatures were of course gone , but they can reset . My new signature appeared as expected under my posts .
But , Then I made a new post and in the textarea at the top was my old signature reappeared. If I submit that post the old signature is there in the post , but the new signature is placed and appears correctly as well. I can of course easily delete the old sig from the textarea before posting and everything is good , but already users of course are getting double sigs old and new . so for users sake this annoyance needs to be removed . I guess it has hungon in the database somewhere or maybe some template , but I cant figure out yet how to get rid off it. When deleting the old signature module , of course there was no facility to uninstal it , so maybe its kept data hanging around somewhere , or maybe the comment module is retaining the data , or maybe its a old signature template somewhere . Can anyone suggest a solution , or some idea where I can look to rid myself of the old signature ghost. Please :)