PPPoE stay connected but with no access????

[perikillo]

  Hi all.
     I was using Freebsd 4.10-p5 very well PPPoE
IPFILTER+IPNAT+gateway, them i decide to test 4.11, and made the
upgrade.

     Ok every thing was find, and again setup my Firewall IPFILTER +
IPNAT + gateway PPPoE, y configured the machine to run PPPoE each time
i turn on the Computer.

      But something start to happend:

      Sometimes the connection dosent respond, my clients could access
the outside world, the link appear to be Up and running:
isp# ifconfig
       tun0
       Public  MyIP ----------------------------> ISP IP
       #PID number

    If i make some test like ping to my clients(Windows 2k and XP):
isp#ping win2kac
-------Respond----------
isp#ping winxp
-------Respond----------

   Then my local network is working.

    But if i test the outside or my DNS:

isp#ping DNS1_IP
----Dosent respond
isp#ping DNS2_IP
----Dosent respond

     But my connection still Up and Running, then i need to manually
close and run again the connection, supposed that went setup ppp to
run over rc.conf  if fails he restart alone, but because it say that
is running he dont restart.

     Went i was using 4.10-p5 i could leave my machine running days
with out any problem.
 
     Some knows if this is 4.11 problem or something change from 4.10
to 4.11, because i setup equal the files, dont see any changes on my
Readme files went i made the upgrade.

     Any idea????

     Thanks all for your time.