I have added in Hebrew into the list of target languages on
http://translate.multibit.org.
It will appear as an option in the list of languages in the next release.
MultiBit does do RTL, though the layout needs a bit of tidying up.
Here is "Hebrew in English" i.e. the GUI is set to Hebrew but all the text is still in English:
(You can see the list of wallets should be on the right and some of the spacing is wrong. Also I am not sure about things like whether BTC should prefix the amount or be postfix. Any "RTLisms" like that you spot just let me know and I will work my way through them).
p.s. that's the test version (with encrypted wallets) not the live version that is on the website.
Punctuation doesn't seem to be handled right.
Synchronized with network.
should be:
Synchronized with network.
This should be fixed, or translators will encounter nasty surprises.