Does changing the MTU on the WAN interface have any effect on the MTU 
over an IPSEC VPN tunnel?

How about changing the MTU of the LAN interface of the M0n0wall on the 
exec.php page with a "ifconfig eth0 mtu 1300"?

Additionally, how does one determine the optimal MTU for transport over 
the tunnel? Is a "ping -f -l 1472" from a DOS prompt sufficient, or will 
this just get split up and reassembled - thus providing a false reading?

I am having a lot of trouble with VPN slowness at one of my locations. I 
just can't figure out why my ping times are good, I am only getting .15% 
packet loss, but things are still much slower than the other locations.

Thanks for any help!
Andy