"xclock -display" from guest vserver to host?



Hi,
My host runs an X server on its display :0
The same host has a vserver running (it is an OS-level virtualization).
Host's name is "gentoo" and the guest vserver is "guest_gen."

Now from the vserver I do:
guest_gen / # xclock -display gentoo:0
Error: Can't open display: gentoo:0

gentoo is reachable because:
guest_gen / # ping gentoo
PING gentoo (192.168.0.4) 56(84) bytes of data.
64 bytes from gentoo (192.168.0.4): icmp_seq=1 ttl=64 time=0.070 ms


and guest_gen can connect to X server on gentoo because:
localhost ~ # xhost
access control disabled, clients can connect from any host
INET:guest_gen


So what is wrong here?
thank you for any answers

Agryppa

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