Poom

hi everyone I am trying to send an email with "Track changes" enabled in Microsoft outlook 2003 . As you can see in the attachment, the icon is greyed out and I don't have a clue how to enable it. In microsoft word it is easy enough , and I have word 2003 enabled as my default email editor , but i cannot find any way to turn it on when composing a new email with outlook. Please help if you can