Arduino IDE won't start on windows XP

hey everybody,
i want to compile the USBKeyboard, for this i need the IDE v0016. v0018 and v0017 working well on my XP. if i try to open v0016 nothing happends.. so i tried all tricks you duiscussing here.. nothing works, not the bat... NOTHING..
it doesnt work on 2 different XP maschines and not on a Windows7
on a Server 2003 it works.
i cant understand anymore. i tried everything of your tips here... the bat gives me following message:

Native lib Version = RXTX-2.1-7
Java lib Version = RXTX-2.1-7
Exception in thread "main"
java.lang.NumberFormatException: null
  at java.lang.Integer.parseInt<Unknown Source>
  at java.lang.Integer.parseInt<Unknown Source>
  at processing.app.Preferences.getInteger<Preferences.java:750>
  at processing.app.Editor.restorePreferences<Editor.java:420>
  at processing.app.Base.<init><Base.java:143>
  at processing.app.Base.main<Base.java:104>

i need really fast help. pls pls pls help me... im close to cry :cry: