We are starting to experience this problem running all the version from 2.9.38 up to 2.9.46.
The customers are logging at same time after a network issue or after a power blackout or after the pppoe concentrator reboot.
We are speaking about 1000 customers over 70 PPPoE servers running on a P4 at 3.2ghz box with 1GB ram.
The only way to recover it is to disable all the servers, rebooting the box and then enabling one server at a time.
Please look into this issue as soon as possible, becuase now the situation is critical.
Regards
Rosario