Problems with VNC Server and Fedora Core 5

[slaterm at geo.net.au]

Hi,
I have been trying to get vncserver working on fc5, and it appears to start
normally from the command line:

>[slaterm at mail ~]$ vncserver 
>New 'mail.domain.net:1 (slaterm)' desktop is mail.domain.net:1
>Starting applications specified in /home/slaterm/.vnc/xstartup
>Log file is /home/slaterm/.vnc/mail.domain.net:1.log
>[slaterm at mail ~]$ 

however the vncserver dies with no error messages except :
>xsetroot:  unable to open display ':1'
>vncconfig: unable to open display ":1"
>twm:  unable to open display ":1"
>xterm Xt error: Can't open display: :1

I read the man page, and couldnt fine any info on debugging switches, or what to
do to correct the problem.

Any Ideas ?

thanks