MINMSS cripples samba server to winXP box

I thought I had troubles with my ethernet card, but it turns out that
the current settings for the following variables are causing me great
pain:

	net.inet.tcp.minmss
	net.inet.tcp.minmssoverload

I have a winXP box that is being served by my FreeBSD system with
samba-3.0.0_1,1.  I don't know if this has anything to do with it, but
the winXP box has some VPN software installed that forced the MTU to be
set down to 1300.

With the default setting of -CURRENT, I will get messages like

kernel: too many small tcp packets from 192.168.10.5:34831, av.
105byte/packet, dropping connection

and smbfs is hosed.  The byte/packet average varies but seems to always
be above 100.

Cheers,
Sean