pon oddities - pop-up windows from ip-up.local, pppstatus

["A. F. Cano" <afc@shibaya.lonestar.org>]

I've decided to automate what I've been doing manually after starting
pppd, via pon.

/usr/bin/pon (a script) starts /usr/sbin/pppd (an suid root executable).
I used to start pon as root, but I've added myself to the dip group
so I now can start it as a regular user.  After the link is up,
/etc/ppp/ip-up.local is executed.  This works to get the mail and
usenet news.

But I would like a window to pop up telling me when that is done, so
I researched a bit and found zenity.  I also wanted to pop up a
konsole with pppstatus running in it.

When running a test script as myself that runs the zenity line:

zenity --info --text="Done getting the news"

it works fine, the window pops up.  But when called from ip-up.local
nothing happens.  The only error in the log file is:

This option is not available. Please see --help for all possible usages.

I've also tried:

su <regular-user> -c 'zenity --info --text="Done getting the news"'

with the same result.  I understand that pppd is suid root and that is
the likely cause of the problem.  I've added DISPLAY=:0.0 before calling
zenity with no effect.

The konsole with pppstatus running in it is called from ip-up.local
like this:

su <regular-user> -c "konsole --vt_sz 80x24 --nomenubar --notabbar --noscrollbar -e pppstatus -s 1540"

I've also tried without su.  The result is the same: 

konsole: cannot connect to X server

And this is even after I've typed

xhost +

from a regular user console.  The X/kde session was started as that user.
I understand that it is a security feature of the X server not to allow
connections from root, but how do I get a window popped up from a
setuid root script?

There is one more oddity.  When ip-up.local is executed, pppstatus started
by hand (as a regular user) thinks that ppp is disconnected/off.  When
ip-up.local is renamed and thus not found/executed, pppstatus has access
and works fine.

Any hints or explanations?

Thanks!

A.