Viewing Arabic messages and web pages works. I've used them personally.

Arabic in modest seems to work too. Someone told me (Can't remember who ;-))

So the fonts are there. What we need is a way to enter arabic which is probably a plugin for the on-screen keyboard.

I wrote a plugin for N810/Diablo but didn't yet have time to port it to Maemo5. I'll try again as soon as the HIM plugins documentation for Maemo5 becomes available.

As for an Arabic UI, I'm not personally interested in that and will not help with the actual work but I can help with packaging and/or bringing interested people together.

It's just a matter of time :-)