I went and dug this up it might help you use kppp without superuser password
On Mon, 10 Nov 2003 22:01:02 -0600, TC typed:
> Under RH9, every time I try to start up KPPP in my user account, it
> requires me to enter the root password to run. What's the secret to
> getting it to run without this intermediate step?
> I've checked the permissions of the KPPP link and it appears to give
> users execute permission. I also found in the KPPP help files something
> about an /etc/KPPP.allow file; however, that did nothing to help either.
As root edit /etc/pam.d/kppp and change the line that reads;
auth sufficient pam_rootok.so
auth sufficient pam_permit.so
Save and exit the file.