Double IP address for tun /dev/tunN

[Andrew]

Hi!

I use /usr/sbin/ppp to connect my FreeBSD-4.10 box to my ADSL provider.
Each time I connect I am assigned a new dynamic IP address. Sometimes I
notice that an old address lingers on for days (through several
reconnects) like this:

satbsd# ifconfig
<...>
tun0: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 1480
        inet 83.237.41.95 --> 83.237.41.1 netmask 0xffffffff
        inet 83.237.23.176 --> 83.237.23.1 netmask 0xffffffff
        Opened by PID 32932
<...>

This address - 83.237.41.95 - has been assigned to me four days ago!
83.237.23.176 this is my current address, and I've had a few addresses
in between.

Here is the reconnect log when the old address remained:

Oct 12 16:07:08 satbsd ppp[32932]: Phase: deflink: open -> lcp
Oct 12 16:07:08 satbsd ppp[32932]: Phase: bundle: Terminate
Oct 12 16:07:11 satbsd ppp[32932]: Phase: deflink: Disconnected!
Oct 12 16:07:11 satbsd ppp[32932]: Phase: deflink: lcp -> logout
Oct 12 16:07:11 satbsd ppp[32932]: Phase: deflink: logout -> hangup
Oct 12 16:07:11 satbsd ppp[32932]: Phase: deflink: Disconnected!
Oct 12 16:07:11 satbsd ppp[32932]: Phase: deflink: Connect time: 86405
secs: 1792934760 octets in, 97733143 octets out
Oct 12 16:07:11 satbsd ppp[32932]: Phase: deflink: 8951000 packets in,
8802534 packets out
Oct 12 16:07:11 satbsd ppp[32932]: Phase:  total 21881 bytes/sec, peak
490137 bytes/sec on Mon Oct 11 18:33:49 2004
Oct 12 16:07:11 satbsd ppp[32932]: Phase: deflink: hangup -> opening
Oct 12 16:07:11 satbsd ppp[32932]: Phase: bundle: Establish
Oct 12 16:07:11 satbsd ppp[32932]: Phase: deflink: Enter pause (3) for
redialing.
Oct 12 16:07:14 satbsd ppp[32932]: Phase: deflink: Connected!
Oct 12 16:07:14 satbsd ppp[32932]: Phase: deflink: opening -> dial
Oct 12 16:07:14 satbsd ppp[32932]: Phase: deflink: dial -> carrier
Oct 12 16:07:15 satbsd ppp[32932]: Phase: Received NGM_PPPOE_ACNAME
(hook "STREAM")
Oct 12 16:07:15 satbsd ppp[32932]: Phase: Received NGM_PPPOE_SESSIONID
Oct 12 16:07:15 satbsd ppp[32932]: Phase: Received NGM_PPPOE_SUCCESS
Oct 12 16:07:15 satbsd ppp[32932]: Phase: deflink: carrier -> login
Oct 12 16:07:15 satbsd ppp[32932]: Phase: deflink: login -> lcp
Oct 12 16:07:16 satbsd ppp[32932]: Warning: deflink: Reducing configured
MRU from 1500 to 1480
Oct 12 16:07:16 satbsd ppp[32932]: Phase: bundle: Authenticate
Oct 12 16:07:16 satbsd ppp[32932]: Phase: deflink: his = CHAP 0x05, mine
= none
Oct 12 16:07:16 satbsd ppp[32932]: Phase: Chap Input: CHALLENGE (16
bytes from A444-rb01)
Oct 12 16:07:16 satbsd ppp[32932]: Phase: Chap Output: RESPONSE
(userpppoemtu)
Oct 12 16:07:16 satbsd ppp[32932]: Phase: Chap Input: SUCCESS
Oct 12 16:07:16 satbsd ppp[32932]: Phase: deflink: lcp -> open
Oct 12 16:07:16 satbsd ppp[32932]: Phase: bundle: Network

This log is perfectly similar to other reconnects, when the address was
changed successfully and the old address didn't linger. Please suggest a
solution to this problem, as some dynamic-ip services refuse to work
because of it.

Thanks,
Andrew P.