resetting network-manager's list of trusted networks

[Matt Price]

hi, 

i seem to have accidentally connected to a neighbour's wireless network
once through gmnome's network-manager applet, and now every time i start
up, NM hooks me up to the neighbour instead of to my own home network.
this is frustrating b/c the neighbour's unsecured network doesn't seem
to have proper DNS (in addition to being somewhat rude).  i'd like to
remove the network from my trusted list, but don't see any info on how
to do this.  any hints?

also -- due to an injury i can't handle high mail volume right now & am
not receiving ubuntu mail.  i'd really appreciate a cc.  thanks,

matt