If you edit a post that contains a link and place a new link where an old one used to be (as in, the same piece of text changing from a link to one url to another), the end result when you save it is no link. This is using the button, the BB tags, as the BB tags have their own linking problems.
Readers: If you need to do this, delete the original text completely and re-enter it until Chucky's able to fix the button.
Readers: If you need to do this, delete the original text completely and re-enter it until Chucky's able to fix the button.