[T#191] Not leveling a particular skill anymore (xp bugged)

If you are having prolonged grinding sessions, you might encounter that a particular mainskill may hang just a few xp before leveling. This may also occur when doing missions.

Say your CON is at 1995/2000 xp and you are doing a mission worth 200 xp, you will not level up. You can do hours of missions - nothing will happen until you:
- do something different (kill or switch weapons or get hit)
- set skillpoints to subskills (not working most of the time)
- relog

You may watch this phenomenom very often at the super hard mission guy on the testserver. One skill may stuck no matter how many rats you kill, until you do something from the above mentioned solutions.