It was a messy to try to export the display to a remote host. Typically it is just matter to use command like xauth <hostname> and set the DISPLAY environment variable properly or better to use ssh forwarding. On Putty and TeraTerm we need just to enable a check instead from a linux shell you can use:
ssh -X -l username hostname
where the -X will perform the magic…check also for the -Y option)…However this on CentOS 5.5 doesn’t work!!!.
This is caused by a bug (http://bugs.centos.org/view.php?id=2391). So to avoid you to spend time finding this bug simply you just need to install the xorg-x11-xauth package.
So to be simple type on the shell:
yum install xorg-x11-xauth