[root@localhost ~]# XAUTHORITY=
[root@localhost ~]# Xvfb :2 -screen 0 800x600x32 -fbdir /tmp &
[1] 13754
[root@localhost ~]# DISPLAY=:2.0 firefox -width 800 -height 600 &
Fatal server error:
Couldn't add screen 0
[root@localhost ~]# DISPLAY=:2.0 firefox -width 800 -height 600 &
[2] 13755
[1]   Exit 1                  Xvfb :2 -screen 0 800x600x32 -fbdir /tmp
[root@localhost ~]# /usr/local/firefox/firefox-bin: error while loading shared libraries: libstdc++.so.5: cannot open shared object file: No such file or directory
[root@localhost ~]# up2date libstdc++

Fetching Obsoletes list for channel: rhel-i386-es-4...

Fetching rpm headers...
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Name                                    Version        Rel
----------------------------------------------------------


The following packages you requested are already updated:
libstdc++
[2]+  Exit 127                DISPLAY=:2.0 firefox -width 800 -height 600
[root@localhost ~]#