ntpd not adjusting the clock?

[Zbigniew Szalbot]

Hello,

Sorry to bother again but I run ntpd on FBSD 6.1 and the clock differes by 
about 30 seconds when I compare the time with top and this link 
http://www.timeanddate.com/worldclock/city.html?n=262

My ntp.conf file looks like that:

server 2.pl.pool.ntp.org prefer
server 1.europe.pool.ntp.org
server 0.europe.pool.ntp.org
restrict default ignore
driftfile /var/db/ntp.drift

The rc.conf file has these lines:
ntpd_enable="YES"
ntpd_flags="-g -c /etc/ntp.conf -p /var/run/ntpd.pid -f /var/db/ntp.drift"

What am I doing wrong that instead of having the time synced I see more 
and more discrepancy. When I rebooted and started the service 6 days ago 
there was about 20 seconds difference. Now it is well over 30.

Many thanks in advance!

--
Zbigniew Szalbot