Using scrub + rdr gre does not work as expected

[Scott Ullrich]

Hi,

We are trying to track down an issue when using the Frickin PPTP
proxy.   When we use "scrub in all random-id fragment reassemble" the
GRE traffic fails to get rdr'd properly.   If we remove the scrub
directive the traffic flows as it should.  Here is a look at the state
list both ways:

With scrub:

self gre 192.168.10.198 <- 192.168.10.1       MULTIPLE:MULTIPLE
self gre 192.168.1.199 -> 192.168.10.1       SINGLE:NO_TRAFFIC
self gre 192.168.10.1 -> 192.168.1.199       MULTIPLE:MULTIPLE

Without scrub:

self gre 127.0.0.1 <- 192.168.10.1 <- 192.168.1.199       NO_TRAFFIC:SINGLE

Also, why is the IP address changing in these states?   We are only
using .199 here as a test.

Anyone have an idea?  This works okay on OpenBSD 3.6.  I am told by
the Frickin PPTP author that it works ok on 6.0 but it appears broken
on 6.2.

FreeBSD pfsense.local 6.2-RELEASE FreeBSD 6.2-RELEASE #0: Fri Jan 12
15:32:48 EST 2007
sullrich at default.domain.com:/usr/obj.pfSense/usr/src/sys/pfSense.6
i386

Thanks in advance!