Random disconnects on 10.0 with mpd5/pptp + PF

[martin i]

Hi all,

I've a FreeBSD 10.0 amd64 r264316 with custom built kernel (GENERIC + PF +
cryptodev/crypto/aesni). I'm using mpd5 to provide pptp access to my samba
shares hosted on the very same machine.
PF is used for filtering/NAT (samba is bind on custom loopback interface
only). All clients are experiencing random disconnects, even during the
active session.

There's no indication in mpd log why the session is closed, I can only see:

Apr 19 00:09:32 foxi mpd: [cloud_b-1] IFACE: Up event
Apr 19 00:16:30 foxi mpd: [cloud_link-1] PPTP call terminated

Devd does log a lot of events:

Apr 18 00:06:01 foxi devd: Executing '/etc/pccard_ether ng0 start'
Apr 18 00:14:23 foxi devd: Executing '/etc/pccard_ether ng0 start'
Apr 18 00:22:46 foxi devd: Executing '/etc/pccard_ether ng0 start'
Apr 18 00:33:47 foxi devd: Executing '/etc/pccard_ether ng0 start'
Apr 18 00:42:09 foxi devd: Executing '/etc/pccard_ether ng0 start'

On apr 17, it was 107 of these messages. Disconnects are random, but
usually the session can't be kept alive for more than 10 minutes. Session
is terminated even during an active session (i.e. when client is copying
data, etc.).

On FreeBSD 9.2 with the same configuration I've no problems.

I can't figure our why is this happening. I was hoping maybe somebody did
already experience the same issues?

Browsing the archive the closest match to my problem is the following:
 http://lists.freebsd.org/pipermail/freebsd-net/2014-February/037864.html

but the patch is (so it seems) already merged to the revision I'm using.

Pls what can I do better to check where the issue is coming from ?

Martin