Admin Custom Text Plugin - extend translation options.

I recently was trying to translate some text form different plugins into my language. Although I can edit easly po. files I caouldn't find all text i need.
Also i'm designing membership site with few friends from different countires, and we'll need to use 3 different languages. That's why i'm investigating options for using different languages.
There's a great Admin Custom Text Plugin that easly translates admin texts. My feature request would be to add option to it, so you could type any text you want to translate on a site (excluding content text).
How it could work - when you make translation it aoutomaticly updates a po. file of particular language that you choose to translate to....
I think that would be very usefull especially in MU sites cause anybody with certain permisions could make changes easly. All without messing around with the code. All in one. What everybody thinks about the idea? Is it possible?