This is also happening on x86_64 Fedora 10 installs.  

I am also seeing this with the new JDK from sun.

Java applications are working on a system that does not have the latest updates.

I can confirm this, neither Sun's JRE nor Fedora's OpenJDK works with my web start applications after I installed the updates

as an additional note: after dumping the cache-folder of java and reinstalling the sun rpms everything works again

I cant reproduce this on an i386 with f10 and the latest java packages using the Notepad.jar demo.

$ java -version
java version "1.6.0_0"
IcedTea6 1.4 (fedora-13.b14.fc10-i386) Runtime Environment (build 1.6.0_0-b14)
OpenJDK Client VM (build 14.0-b08, mixed mode)
$ rpm -q java-1.6.0-openjdk
java-1.6.0-openjdk-1.6.0.0-13.b14.fc10.i386

Unable to reproduce with java-1.6.0-openjdk-1.6.0.0-11.b14.fc10.i386.

Ok, starting work this morning, I see that it is not Java, but it looks that an imsettings is going to futex wait. Once I killed that process, java applications worked.  This morning I had a lot of applications not work including citrix, VirutalBox and my Java applications.  Once I killed the imsettings that was in futex wait, everything started fine.

(In reply to comment #7)
> Ok, starting work this morning, I see that it is not Java, but it looks that an
> imsettings is going to futex wait. Once I killed that process, java
> applications worked.  This morning I had a lot of applications not work
> including citrix, VirutalBox and my Java applications.  Once I killed the
> imsettings that was in futex wait, everything started fine.  

Easiest way to reproduce at least in my case is with Sun's JDK and jcontrol. 
[mos@fault ~]$ ps xauw|grep imsettings
mos       3374  0.0  0.6  21480  7180 ?        S    20:59   0:00 imsettings-applet --disable-xsettings
mos       3798  0.0  0.0   5156   708 pts/0    S+   21:05   0:00 grep imsettings
[mos@fault ~]$ strace -p 3374
Process 3374 attached - interrupt to quit
restart_syscall(<... resuming interrupted call ...>^C <unfinished ...>
Process 3374 detached
[mos@fault ~]$ cd /usr/java/latest/bin/

And running jcontrol with strace produces dialog window that is frozen and strace shows:
mprotect(0xb7f1c000, 4096, PROT_NONE)   = 0
clone(child_stack=0xb7f6c4b4, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, parent_tidptr=0xb7f6cbd8, {entry_number:6, base_addr:0xb7f6cb90, limit:1048575, seg_32bit:1, contents:0, read_exec_only:0, limit_in_pages:1, seg_not_present:0, useable:1}, child_tidptr=0xb7f6cbd8) = 3812
futex(0xb7f6cbd8, FUTEX_WAIT, 3812, NULL

And strace on the imsettings is now:
[mos@fault ~]$ strace -p 3374
Process 3374 attached - interrupt to quit
futex(0xf01140, FUTEX_WAIT_PRIVATE, 2, NULL

Killing both jcontrol and imsettings and then restarting jcontrol produces running jcontrol. 

I think this is very critical issue, as it makes me also unable to play Ticket To Ride or Asobrain Explores without killing imsettings-applet. Both very addictive applet-based web games!

(In reply to comment #8)
> 
> Easiest way to reproduce at least in my case is with Sun's JDK and jcontrol. 
> [mos@fault ~]$ ps xauw|grep imsettings
> mos       3374  0.0  0.6  21480  7180 ?        S    20:59   0:00
> imsettings-applet --disable-xsettings
> mos       3798  0.0  0.0   5156   708 pts/0    S+   21:05   0:00 grep
> imsettings
> [mos@fault ~]$ strace -p 3374
> Process 3374 attached - interrupt to quit
> restart_syscall(<... resuming interrupted call ...>^C <unfinished ...>
> Process 3374 detached
> [mos@fault ~]$ cd /usr/java/latest/bin/

Unfortunately, I have never used SCIM before. I am going to need a little help reproducing this. I used System->Preferences->Personal->Input Method to turn on SCIM. I logged out and back in.
$ ps aux | grep [i]msettings
omajid   20887  0.0  1.0  32072 10452 ?        S    10:01   0:01 imsettings-applet --disable-xsettings
$ /usr/java/latest/bin/jcontrol 
This works without any issues. I tried changing the input language through the gnome applet but it didnt seem to have any effect.

This bug just started happening with the latest GTK update.  Java applets and web applications that use 2d rendering are affected under Gnome.  When I switched to KDE, everything works just fine as a work around.

This may also be a duplicate of bug #491813

*** Bug 492335 has been marked as a duplicate of this bug. ***

(In reply to comment #9)
> 
> Unfortunately, I have never used SCIM before. I am going to need a little help
> reproducing this. I used System->Preferences->Personal->Input Method to turn on
> SCIM. I logged out and back in.
> $ ps aux | grep [i]msettings
> omajid   20887  0.0  1.0  32072 10452 ?        S    10:01   0:01
> imsettings-applet --disable-xsettings
> $ /usr/java/latest/bin/jcontrol 
> This works without any issues. I tried changing the input language through the
> gnome applet but it didnt seem to have any effect.  

I had not enabled SCIM or did not even know what it was. But as I enabled it, logged in and logged out the jcontrol started working without hanging.

New updates have been released for both libX11 and imsettings. Does this problem still persist even after installing the updates?

With the new LibX11 and imsettings, that fixed the problem.  Java no longer hangs.

When loading up applet in Java game cribbage, it loads up but not abel to play.

(In reply to comment #15)
> When loading up applet in Java game cribbage, it loads up but not abel to play.

(In reply to comment #15)
> When loading up applet in Java game cribbage, it loads up but not abel to play.

This is currently reproducable by building the Scala language compiler from SVN in VirtualBox (www.virtualbox.org).

Scala's build uses Java (1.6.0_20).

Hi, 
Good to find/read/know this, what's the solution for this? Thanks.