We have a user entering tags in the news module that contain '. When he enters the tags as a new tag it works fine. If he then wants to add that tag to a second news item, when clicking on the tag in the tag list we get this error:
This only occurs with the tags containing single quotes.
I've found that the way around this is that instead of selecting the tag from the list, if the same tag name is entered via the add new tag dialog, it selects the existing tag rather than adding a new one of the same name. Using this method allows for the single quote containing tags to be selected.