Prevent Wireless Connction to Rouge WAP?

I have a neigbor broadcasting his SSID and one of my
Servers keeps picking up the network and trying to
connect to the other wireless network.

I need to know how to disable/prevent this.

I've unchecked the box that says "Automatically connect
to non-preferred networks" and I tried chaging my channel
on the WAP from 6 to 9 - it still appears to be an issue.

The behavior is that you get the pop-up that
says "Wireless networks are available" Click here to view
them - and it kicks me off my own WAP until I click the
popup and click "connect" again.

Help!