The Xsession file installed and used by net-misc/x2goserver (/etc/x2go/Xsession) calls xmodmap and setxkbmap to setup the session keyboard, but net-misc/x2goserver does not RDEPEND on x11-apps/xmodmap and x11-apps/setxkbmap so they might not be installed on the server system. In this case, the keyboard settings inside a x2go session will be wrong. That's why net-misc/x2goserver should RDEPEND on x11-apps/xmodmap and x11-apps/setxkbmap so the session keyboard is configured correctly. For similar reasons, the package possibly should also RDEPEND on x11-apps/xrdb. However, a missing xrdb usually causes no obvious problems.
+1 /usr/bin/x2gosetkeyboard also calls setxkbmap.