xdm and su xauth problem

[Lubos Vrbka <lists@vrbka.net>]

hi guys,

this is probably some stupid mistake or omission i made...

so far, i was starting X using the startx command (i.e., under ordinary 
user). recently i installed xdm to handle my logins (so X is now started 
under root, i guess). everything works fine except that after login as 
an ordinary user...

$ su
Password:
# xeyes
Xlib: connection to ":0.0" refused by server
Xlib: No protocol specified
Error: Can't open display: :0.0

surely, running
xhost +
remedies this problem, but that doesn't seem to me as a good solution... 
so what should i do to get it back working?

thank you for any hints. best regards,

--
Lubos _@_"
http://www.lubos.vrbka.net