Note that vncv supports only version 3.3.

Reference: /n/sources/patch/applied/vncv-version
Date: Thu Nov 11 22:07:57 CET 2010
Signed-off-by: a@9srv.net

--- /sys/man/1/vnc	Thu Nov 11 22:02:25 2010
+++ /sys/man/1/vnc	Thu Nov 11 22:02:20 2010
@@ -232,3 +232,6 @@
 .I Vncv
 does no verification of the TLS certificate presented
 by the server.
+.PP
+.I Vncv
+supports only version 3.3 of the RFB protocol.