slowoffice doesn't work

[Wojciech Puchar]

trying to start openoffice shows:

[wojtek at wojtek ~]$ openoffice-3.4.0-swriter
XDM authorization key matches an existing 
client!/usr/local/openoffice-3.4.0/openoffice.org3/program/soffice.bin X11 
error: Can't open display:
    Set DISPLAY environment variable, use -display option
    or check permissions of your X-Server
    (See "man X" resp. "man xhost" for details)



everything else works, doing

xhost +

"fixed" the problem. any idea what is wrong.
deleting .openoffice doesn't change anything