XOs on AP unpingable after wakeup/startup

[Morgan Collett]

I've got 4 C2s on my access point running joyride - currently 2200 and
2210. If I power them on, or wake up from a power-button-induced
sleep, and make sure they are on my AP, they will see each other with
salut (multicast) but not be able to connect to my jabber server or be
pingable from other hosts on my WLAN. I get "Destination Host
Unreachable". I get the same result (Destination Host Unreachable) if
I try to ping my laptop from one of the XOs.

If I ping them from my laptop it takes somewhere between 100 and 300
packets before they start responding. Then usually they start
responding to ping, ssh, etc and can access the jabber server (on my
laptop). Some times I don't manage to get one or more of them
connected without rebooting.

Other devices on my network (2 PCs and an N810) are pingable as soon
as they are on the network.

Is this a known issue? Could it be my access point (a Mercury KOB
WL465, not that I expect to find anyone else with one...)?