FreeBSD 8.2 and MPD5 stability issues

[Adrian Minta]

Hello,
I am testing a RAS solution and I experience some crashes when the L2TP 
tunnels grow above 3500. The IPv6 is disabled on the box. With IPv6 
enabled the limit is around 1700 (half). Does anyone has a sugesstion 
what I should try next ?

total traffic: ~ 100mbps
load averages: ~1.8


Kernel: FreeBSD 8.2-RELEASE
MPD5:    mpd-5.5

/boot/loader.conf
net.graph.maxdata=65536
net.graph.maxalloc=65536
kern.ipc.maxpipekva=320000000

/etc/sysctl.conf
net.inet.ip.forwarding=1
kern.maxfiles=65535
net.inet.icmp.icmplim=0
net.inet.ip.fastforwarding=1
kern.ipc.nmbclusters=1280000
kern.ipc.maxsockbuf=128000000
net.graph.maxdgram=10240000
net.graph.recvspace=10240000

-- 
Best regards,
Adrian Minta    MA3173-RIPE
tel. +4.0212.022.660 +4.0726.110.369