Description:
If you use auto-wireless detection and have a wireless network profile that whose essid starting with an available access point's essid, then netcfg will attempt to start that profile. For example, when I scan for wireless networks at home, either at boot or using /etc/rc.d/net-profiles restart, then the below profile attempts to start. This is because there is an AP with an essid of "work" in my neighborhood.

Additional info:
* netcfg 2.0.6-1
* /etc/network.d/work:
CONNECTION="wireless"
DESCRIPTION="work wireless connection"
INTERFACE=wlan0
SCAN="yes"
ESSID="work-official-wireless"
IP="dhcp"

Steps to reproduce:
Scan your area for wireless networks.
Create a profile whose essid starts with the essid of an AP you can see. So if you found "wireless", you might give your profile an essid of "wireless-network". Note that my testing shows the '-' is not necessary; you could name your profile "wirelessnetwork" just as well.
Have your /etc/rc.conf set to NETWORKS=(auto-wireless <interface>)
Restart net-profiles
The profile you just created should be brought up.