I'm just passing along some info Victor helped us with during an upgrade to 1.2.5.

Our environment is Ubuntu 12.04/tomcat6.  When we upgraded from 1.2.4 to 1.2.5 we encountered this message when logging in to the thin client (see attached image):

  'Load MIB file on startup' has encountered a problem.  An internal error occurred during: "Load MIB file on startup".  Java heap space.

This may be obvious to some, but I thought I would post the solution here in case it will help someone in the future.  This is due to a tomcat stack size being configured too small on your server.  On Ubuntu 12.x, the right place to change this is:

    /etc/default/tomcat

Modify the JAVA_OPTS line in this file to increase the stack sizes (Xms and Xmx):

  JAVA_OPTS="-Djava.awt.headless=true -Xms1024m -Xmx2048m -XX:+UseConcMarkSweepGC"

Make sure you "un-comment" this line if it has a hash-tag in front of it.

Restart tomcat ("sudo /etc/init.d/tomcat6" restart OR "sudo service tomcat6 restart") and you should be all set.

Hope this helps someone along the way.