I presume of course that I would firstly need to install VNC on the server side ( I am guessing it is not part of a standard install footprint for Linux ) ?
This will install a VNC server, Xterm and the Tiny Window Manager, just enough for the VNC server to launch Xterm and display the OUI and its various dialog boxes.
# yum install tigervnc-server xterm xorg-x11-twm
By the same measure I am guessing the XLib's to enable an X Server to be launched remotely are included as part of a standard install footprint for the Linux server ?
That will install all the required dependencies for Oracle Database, including all the X libraries that are required.
# yum install oracle-rdbms-server-11gR2-preinstall