I have found a solution for this and fixed it in my local copy. I guess I will be putting out a minor new release very soon to fix this and to get the new image resizing function into the hands of users.
Another thing I fixed a few days ago was an issue where since I changed to TinyMCE on this site people would post code and errors in the forums and it could make the page not validate. In FCKeditor I already had an option to force paste as plain text in the forum and now I have also implemented this in TinyMCE.
Best,
Joe