[jitter] Jitter error msg mxj/jvm

Hey there,

I've just installed the demo version of Jitter and trying to do the first few tutorials, but when I load the first patch I get these messages. Seems like some java stuff is missing:

error: mxj: no such object
error: Jitter Java support: could not find jvm
error: panel: no such object 
error: #X: no such object (quite a few times)

Anyone familiar with this problem ?
Running maxMSP 4.5 + Jitter 1.63, Windows XP SP2