I am using SUSE 10.2 x86_64 with Nvidia FX5500 driver installed.
Firefox 2.0 does not take keyboard input after a while without any keyboard input, or just opened tab. It is kind of random. I cannot tell exactly when it is happening. Firefox is installed from SUSE DVD.
I don't know whether it is Firefox problem or SUSE problem. I am using Firefox 2.0 on Mandriva 2006 too but I don't see the problem with that system. I don't encounter this problem either with the downloaded firefox from mozilla.org. The difference between the stock firefox and downloaded one is plugins. I didn't install any plugin to test downloaded version.

Is this problem somehow related to plugins or any other things? Anybody is encountering the same problem here?

The installed plugins for stock firefox are Flash player, Adobe reader, RealPlayer.

Although it is very annoying, there is a work around on this problem. Just click on the desk top or other application with the mouse and back to firefox, then firefox takes keyboard input again.

I think I found the source of the problem. If I remove the flashplayer plugin there is no problem that I originally reported. When the flashplayer is loaded the following error pops up in the console in which firefox was executed.

Flash Player: Warning: environment variable G_FILENAME_ENCODING is set and is not UTF-8

When this warning pops up firefox does not take keyboard input.
So I guess, if I change 'G_FILENAME_ENCODING' variable to UTF-8 the problem will be fixed. But I don't know how.
How do I change this variable?

Thanks in advance for help.

Well, It seems I found the solution.
Since I am bilingual, multiple languages , English and Korean, are set in /etc/sysconfig/language.
I don't know whether the order is matter in INSTALLED_LANGUAGES variable but it was INSTALLED_LANGUAGES="ko_KR, en_US" before. I changed the order to "en_US, ko_KR".
I also changed the value for AUTO_DETECT_UTF8="no" to "yes".
After these changes Firefox works fine with flash plugin 9.0.
No more hick-up with keyboard input.

Does the flash player plugin for Firefox work fine for you on x86_64?
How did you install it, or where from? This link http://forums.mozillazine.org/viewtopic.php?t=320838 says that Flash does not work with 64bit browsers.

I don't know whether Firefox is 64bit or not but it works with flash plugin 9.0.
My system is SUSE 10.2 x86_64.

Are you running Mandriva 2006 on x86_64? Is the Flash plugin working alright there?