Ah, I think I found out why: (google is your friend)
http://www.psg.com/~brian/doc/comms/ppp.htm

--It all depends on who owns the pppd:
' whereis pppd '
pppd: /usr/sbin/pppd /usr/share/man/man8/pppd.8.gz

' ls -l /usr/sbin/pppd '
Code:
-rwxr-x---    1 root     dip        234504 Nov 24  2002 /usr/sbin/pppd*
--I checked my old /etc/group for SuSE and my userid was in groups "dialout" and "modem." So wvdial must have been owned by one of those groups, as well as pppd. I presume you're using dip as your dialout method; I always used kppp at first, then wvdial on-demand (Server does the dialing when it gets a Squid HTTP request) until I got DSL, which uses pppoe.

--Ah, I think I get it now. When I was using dialup, I always started teh internet connection as root, and all other users could access the connection. Are you starting the dialer as the non-root user?

Quote Originally Posted by bongski55
I found a remedy for my problem. I created a group 'dip' and added that group to my non root user.

Everything is okay now.