[c-nsp] Cisco 7206 - L2TP Tunnel Problem after tunnel clear / lots of wt-con

[Mike]

Hi,

we have about  500 vpdn-sessions (dsl-user) terminated on a 7206 
Cisco-Router running  IOS Version 12.2(16)B2. Everything works fine, until 
the l2tp tunnel will be resettet (got some problems with our carrier in the 
past).
If the tunnel gets resettet, the sessions come in again very quick, gets 
authenticated by radius but a lot of the sessions have the state "wt-con" 
when i take a look at "show vpdn"
These sessions just "hang" , they dont drop and come in again.
We found one setting, but this is only a simple workaround:
if our carrier splits the tunnel into seperate smaller tunnels (each tunnel 
has 100 vpdn-sessions) the sessions will be terminated correctly and there 
are no more sessions with the "wt-con" state.
What can be the reason for this lots of "wt-con" vpdn-sessions? Any ideas ? 
How can i avoid this ?