Installing aftermarket stereo into 1998 Primera

Hi all,
I just brought a 1998 Nissan Primera 2.0L MAN, and have also brought a new stereo for it. I just brought a PIONEER DEH-P5950. I removed the old factory stereo from the car, removed the data connector and antenna, and noticed that the antenna connector has two pins and a gnd shield, one of the pins is for the RF signal and the other will be a signal to the antenna motor telling it to either pull the antenna down or push it out.

thats all fine, the problem lies in the new stereo, its antenna socket is a signal pin connector for the RF signal. So my question to you is how do i convert the old 2pin plug into this 1pin connector so that the signal from the antenna will reach the stereo... and the aerial will still function as normal.:banghead:

Any help would be greatly appreciated.

Thanks