>  What are your ipf settings (fr_ifpaddr is in ipf code)?
>  Does 'pppd noauth 172.16.10.1:172.16.10.2 pty "pppd notty noauth"' work?
>  (It does on my system.)

Well, apparently this crash has something to do with NAT.
I have following ipnat.conf:
map ppp0 192.168.0.0/24 -> 0/32 proxy port ftp ftp/tcp
map ppp0 192.168.0.0/24 -> 0/32 portmap tcp/udp 40000:60000
map ppp0 192.168.0.0/24 -> 0/32

executing 'pppd noauth 172.16.10.1:172.16.10.2 pty "pppd notty noauth"' works.
Moreover after that I can pppd call my provider any number of times.
But NAT stops functioning and even executing '/etc/rc.d/ipnat restart' does not repair NAT.

-- denis