RichEdit font change changes all existing text

With the RichEdit control if I change the font without first selecting
some text then all the text in the edit screen changes to the new font
(or color). This happends with the Font or DefAttributes properties.
I'm running Delphi 5 on windows 98.
What I want to happen is after I change the font any new text is in
the new font but the existing text shouldn't change.
/ Ian