Essentially, the RTE uses "top.document.getElementById(editorId)" to get the editor object. "top" references your web page in the normal scenario, but if you're page is within a frame "top" references the top most web page -
if this web page doesn't have an element with the same ID (which it won't :)) the call fails.
Because I'm naturally cautious changing anything - I decided to create a function that checks if "top" properly references a web page with this element ID in it, if so, the function returns that element, if not it returns the element in the
I then changed everywhere that calls top.document.getElementById to this call this new function and bingo - RTE now works in frames!