KNetworkManager won't detect a router reboot

How can I tell KNetworkManager my wifi is no longer available after a router reboot? It just keeps merrily choogling along with a green icon and all, although my WLAN is as dead as a dead horse. So it doesn’t even try to reconnect because it’s blissfully unaware it’s no longer connected.
And by the way: why does it keep changing its notification icon from a blue/grey “signal column chart” to a green circle and vice versa on a completely random basis?
Anyone know?

I have a similar problem. Not only does KNetworkManager not detect when my router is off (it thinks it’s still connected), it will sometimes allow the connection to die (i.e., the interface is down) but it still indicates it is connected (and at full signal)! I suspect this is a bug in the KDE 3.x KNetworkManager. Gnome’s NetworkManager seems to work better, and I hear better things of KDE 4’s upcoming KNetworkManager. We’ll see.

Shudder! This is starting to feel uncannily like Vista…