problems with z8encore development kit

Hi,

recently I've bought z8 encore development kit, but i have some problem with it.
Every time i touch any of GND,+3.3V, 5V or 9V wires with something made of metal, my system is restarting.
I know, that any signal nets never shouldn't be directly touched, but system ground (or VCC) very often is connected to some sensors, buses, peripherals (the simplest example is ordinary RS232 cable connected to PC). I don't want my system to restart when I just plug the RS232 cable to it.
Does any of you had simmilar problem?
How to deal with it?

Thanks for any suggestions.

regards,
Krzysiek

Z8F642X FIX some problem!

Maybe you can try a new version Z8ENCORE mcu---Z8F642x

It had change some function,like "VBO" option,make user can disable the function.

and well noise resisit.