X server crashing after DB2 installation

Hello,

I got an issue concerning a X server crash and "strange" behaviour (like backspace not erasing written stuff in terminal/console but rewriting letters backwards. e.g. hello world/ /dlrow olleh).

This behaviour first appeared on different machines where I installed DB2 v10.1 Enterprise. On machines where DB2 is not installed, these issues are not appearing. I am using RHEL 6.5.

I attached the Xorg.0.log.
Since I am a rather unexperienced Linux user I hope you can forgive me if a solution might be obvious.