This is an old revision of the document!
zypper ar obs://X11:RemoteDesktop:x2go/openSUSE_12.3 x2go
Substitute openSUSE_12.3 by the tag for the distribution you are actually using. Available ones are: openSUSE_Factory, openSUSE_12.2, openSUSE_12.3 and SLE_11 (SLES 11 SP2).
Congratulations, you are now able to access the X2Go packages. You may continue by installing x2goserver, x2goclient or pyhoca-gui or any other of the available packages.
zypper in x2goclient