I got the fonts for Cambodian installed on mine and it display quite well. But would be nice if someone could porting KhmerUnicode from windows to Maemo 5 would be nice. So I can type Cambodian on my device

Yes, I am. And I tried this on several applications...

About the SYM key... it's an known issue and should be fixed in a couple of weeks. The only current workaround is to uninstall mscim. More info in the issues section of the project: http://code.google.com/p/scim-for-maemo/

at a terminal type:
ps faux | grep scim

and make sure that the scim daemon is indeed running.
it should return this:

thats GREAT news about the Sym key! scim broke it (as well as sticky Caps/Alt) on the 810 -i didnt think anyone cared =]

I already uninstalled it. Since programming on the N900 is for me a much higher priority than entering Japanese text (at least for now), I'll wait for a fix and try again later. Thanks for helping, anyway!

Last week I gave CJK on maemo another try.

I installed maemocjk-him-scim-anthy on my N900 (PR1.2), but it wasn't working. There was no icon in the application menu or in the settings, and there was no "scim" or "anthy" process running, even after more than one reboot...

I even run (from console) imscim and scim-setup, but it also didn't work.

The only change I could notice after installing the package is that the virtual keyboard is not working anymore.

I noticed that the file /etc/gtk-2.0/gtk.immodules should be replaced by a command in the /etc/event.d/scim script, but even after running the command manually, the file is overwritten with the original contents and dated as "Dec 31 1969" after a reboot.

Does anyone have any idea of what can be wrong?

Answering myself (just to help someone in the same situation):

My phone battery died and, after booting and selecting UK as the default region, SCIM started working! According to Kimitake, SCIM works only when you select US/UK English as the 1st language, so maybe something was different in my configuration... Anyway, if you need more tips, visit the posts and read the comments on his blog here, here and here.

Thanks Ricardo, finally got it working!
mamemocjk-him-scim-anthy is a good solution to my japanese dictionary woes, but not a perfect one. I have a couple of remarks/questions:
1. GUI of anthy looks a bit "off" on my N900, some buttons overlap, etc. It seems that the GUI has been designed for some other resolution, and hastily ported to N900. Can it be changed? I might have a go since I've done some GTK programming, but only on Windows, none on N900. Any opinions, where to start, how difficult would it be, etc?
2. Is there a way to use anthy without having to close the HW keyboard?

Now, related to the reason as to why I need japanese input (learning japanese!), I would appreciate very much if somebody could advise me about this:
1. Which dictionary would you recommend for Japanese? I am using MStarDict, with JEDict, I'm but not entirely happy with the verbosity of entries and with the size of vocabulary.
2. Is there some software for searching kanjis, based on radicals (e.g. like at jisho.org), or by a direct input?

Many thanks!

Gjiten (warning, extras-devel) is a good japanese dictionary, it even has search by radical, if you want to give handwriting a try, install Kanjipad too (isn't on the repositories, so you'll have to find an armel .deb)

EBDict is good if you have EPWing dictionaries in the proper format, though it's UI isn't exactly great on the N900 outside of EasyDebian.

Also:

- The SCIM method is very much a statically sized window, and would need a rework for Maemo. Placing it in the status area would probably be a good idea. I don't think that would be too terribly hard, but if you're going for that then reworking the config dialog is probably in order as well.

- In all oddities, for me it works great with the hardware keyboard. I can hit ctrl+shift to switch between English and Japanese input. The only problem is eventually the text input loses focus and I have to flip out and back into the program for it to recatch. It also kills the hold for the blue arrow (->) key, and disables the symbol menu completely when in a program that has the IM module active.

I'd love to see more hands on this project, as I'm going to Japan for 2 weeks in August and would love to have fully functional input by then

Did I help in any way? You're welcome... but the irony of it is that it is not working anymore for me, and I can't imagine why!

I'll second fwrnando's suggestion about Gjiten - it's a bit buggy, but still very good.

About kanjipad... I'll try this later.