starter button relay.

HI all!

I've just completed a starter button mod in my 2002 E47 M3.

I used the Honda switch from an S200, looks great!

trouble is when the ignition is on (driving) its possible to accidentaly press the button and its still active, is there a way to wire a relay to make the button inactive while the engine is running by possibly adding a second relay?

My wiring is........12v swiched live to pin  30, wire out to starter, pin 87,push button switch ,pin 86, ground and button ground to pin 85.

Thanks guys.

Sorry for the double post, i only pressed once...honest.

Mods please delete.

Thanks