When I look at Arabic, Chinese or Japanese text all I see are some odd squiggles. Some text that used to produce square-looking squiggles in KDE 3 now produces more curvy squiggles in KDE 4. Apparently this is a good thing. Most of this is down to Qt 4. But I still don't know whether it is readable to people who normally see something other than squiggles.
I had a stab at adding input method event support to Konsole in trunk recently, but I am very limited in my ability to test it. There is a bug report to file comments against.
If you can read and write in these languages, or even better, understand the mysterious world of Unicode - please help me to find bugs in Konsole's language support so that I can fix them.