Thank you, but where I can find the source code for MIUI? it's open source? if not how are going to do it?
Sorry for the late answer, I've been a bit busy on the last days.
So, MIUI isn't open sourced but you can always decompile the java code with dex2jar.
Until now I've been using a script made by some Israeli devs that automatically fixed the RTL problems, but since version 1.4.8 the Chinese devs have made some changes to one of the files that were overwritten by the script leading to code conflicts so this way is no longer possible.
I'm working together with other devs right now trying to edit the code so the RTL patch and the changes made by the Chinese devs can live together. In addition we're in contact with one of the devs of the new improved RTL code in CM7 and will try to implement it to MIUI. Once we'll have the whole code ready we're even planning to send it to the Chinese devs hoping they'll implement it hard-coded to MIUI, it's a long shot intent but worth trying. I'll let you all know so everyone will put his "+1" on that in the MIUI.cn forums.