I found this in google
Try the following:
chmod u+s /usr/sbin/kppp
ln -s /usr/sbin/kppp /usr/bin/kppp
The first line removes a symbolic link to the real binary. The second line changes the permissions on kppp so that it will run as root no matter what user runs the program. The last line re-creates the link that you removed in the first step. The net effect is that the binary runs as root, no matter what the UID of the user running the program. This means that you don't have to supply a root password.
Please be aware of what you're doing, though. Many security holes are the result of fooling a program with root permissions into behaving poorly. If kppp can be manipulated with spurious input, arbitrary code might be made executable with root permissions. I have no idea of the degree to which kppp is (or is not) susceptible to being abused in this fashion.
That fixed it for me.