RTL languages

Here is the thing; me and some guys have build stuff in flash.

Next we had to make whatever we had developed international (or better multinational since it needed to be distributed in a few countries). Some of these countries used exotic characters and which we could solve with codepages (and since a short while with the so called unicode support).

No problem so far...

HOWEVER now countries with exotic formats have shown interest.
By browsing around i learned that RTL languages are a bit problematic.

Since i dont feel like reinventing everything from scratch and im pretty sure you guys have lots of knowledge, my questions are:

-What do i need to know?
-What are the best practices?
-How about other more exotic formats (Bottom to Top)?

Thx!

PS im working with
-dynamic texts (mostly from XML)
-Static text
-Third party MovieClips (the third party should be able to make RTL movies pretty easy)