Anyone heard of this problem?

When using the "track changes" feature in Word 2007 there doesn't seem to be a way of accepting the changes once and for all. For example, changes are being tracked, then when finally happy one clicks on the "accept all changes" tab. Then all the changes made and comments disappear and the document looks "normal", so is saved as usual.

However, I'm finding when the document is re-opened, it is displayed with all the changes again being shown tracked! Is this a bug? - or is there another tab or method of ensureing once changes are accepted and the document saved, the changes that were made cannot ever be viewed again?