Problem viztracker values

[befl0]

The code to access to the vrpn tracker is :

def bigAndSmall():
	while True:
		yield viztask.waitTime(0.0001)
		x, z, y, h, p, r, ang_der, ang_izq = tracker.getData()

And the error is : File "viztracker.py", line 56, in bigAndSmall
x, z, y, h, p, r, ang_der, ang_izq = tracker.getData()
ValueError: too many values to unpack
check_vrpn_cookie(): VRPN Note: minor version number doesn't match: (prefer 'vrpn: ver. 07.31', got 'vrpn: ver. 07.30 0'). This is not normally a problem.

Thanks,