I do not think you'd want to try using rhodium ubuntu to do those modifications. (Rhobuntu seems... really hard to use at this point. Touchscreen's weird, keyboard's weird, screen's compressed all to hell.)
There is a way to replace your system.sqsh with a system.ext2 (i.e. a standard, rewritable linux filesystem). Then you'll be able to modify it. On the downside, instead of taking up 50mb on your sdcard, it'll take up 250; it also might be more likely to get corrupted if your phone crashes, so make a backup.
Here's the
thread from xda-developers with an app that'll help you do it. I haven't used this myself, but a couple folks from the Touch Pro Android thread have been successful. Good luck. I know a number of people have been looking for Asian font support -- I've just been ignoring them, because I had no idea.
