Ubuntu 15.10 beta 'java' received an X Window System error Freemind not working

Question

I just upgraded to Ubuntu 15.10 Beta. The only problem is related Freemind and Java This is my Installation:

lsb_release -rd
Description:    Ubuntu Wily Werewolf (development branch)
Release:    15.10

freemind

Picked up JAVA_TOOL_OPTIONS:

 -javaagent:/usr/share/java/jayatanaag.jar 
 Checking Java Version...
 The program 'java' received an X Window System error.

This probably reflects a bug in the program. The error was 'BadValue (integer parameter out of range for operation)'.

((Details: serial 117 error_code 2 request_code 138 minor_code 2) (Note to programmers: normally, X errors are reported asynchronously; that is, you will receive the error a while after causing it. To debug your program, run it with the --sync command line option to change this behavior. You can then get a meaningful backtrace from your debugger if you break on the gdk_x_error() function.)

The question is: Why is this a random error? Sometimes Freemind gets started with the following errors:

STDERR: Unable to set Look & Feel.
STDOUT: text
STDOUT: list
STDOUT: list
STDOUT: list
STDOUT: list
STDOUT: list
STDOUT: list
STDOUT: list
STDOUT: list
STDOUT: list
STDOUT: list
STDOUT: page tab list
STDERR: Exception in thread "Thread-1" 
STDERR: java.lang.NullPointerException
STDERR: Exception in thread "Thread-8" 
STDERR: java.lang.NullPointerException
STDERR: Exception in thread "Thread-14" 
STDERR: java.lang.NullPointerException
STDERR: Exception in thread "Thread-15" 
STDERR: java.lang.NullPointerException
STDERR: Exception in thread "Thread-16" 
STDERR: java.lang.NullPointerException
STDERR: Exception in thread "Thread-18" 
STDERR: java.lang.NullPointerException
STDERR: Exception in thread "Thread-20" 
STDERR: java.lang.NullPointerException
STDERR: Exception in thread "Thread-27" 
STDERR: java.lang.NullPointerException
STDERR: Exception in thread "Thread-28" 
STDERR: java.lang.NullPointerException
STDERR: Exception in thread "Thread-30" 
STDERR: java.lang.NullPointerException
STDERR: Exception in thread "Thread-32" 
STDERR: java.lang.NullPointerException
STDERR: Exception in thread "Thread-35" 
STDERR: java.lang.NullPointerException
STDERR: Exception in thread "Thread-36" 
STDERR: java.lang.NullPointerException
STDERR: Exception in thread "Thread-37" 
STDERR: java.lang.NullPointerException
STDERR: Exception in thread "Thread-38" 
STDERR: java.lang.NullPointerException
STDERR: Exception in thread "Thread-39" 
STDER