CEF table on 3750 contains inactive next-hops

Hello Everyone,

I have policy based routing setup on our 3750s located at 4 remote
sites. I have setup the policy based routing with "set ip next-hop
verify-availability" option and also enabled CDP on the 3750 and the
next-hop (WAAS engine).
Here comes the weird bit. In case the WAAS engine fails, the 3750
should stop policy routing. This failover works at one of our sites
but the other 3 sites loose all their connectivity. This is because
the 3750 is still forwarding packets to the inactive WAAS engine.

I checked the CDP neighbor list and the engine is not listed in it
when its down. But the engine is still listed at the next hop in the
CEF table (show ip cef).

I have tried disabling ip route-cache cef on the interface but that
didn't help. I also compared the configs on all 3750s and they look no
different.

I need some urgent help here. This issue is like a disaster waiting to
happen.

All the 3750s are running : IOS (tm) C3750 Software (C3750-I5-M),
Version 12.2(20)SE4, RELEASE SOFTWARE (fc1)

regards
Ankit