redirecting VNC to specific desktop

I have the following entries in my .fvwm2rc

a menu entry

+ "self VNC" Exec vncviewer -shared -name VNC -passwd ~/.vnc/passwd poseidon:1

and a style

Style VNC           StartsOnDesk 2, SkipMapping, NoTitle, NoHandles

these work fine on my old opensuse 11.3 with TightVNC and fvwm 2.5.26. I use them occasionally to get desktop screendumps. This opens a VNC desktop on same machine in desk 2.

When moving to opensuse leap 42 with TigerVNC and fvwm 2.6.6, the style is not honoured (the VNC does not go to desk 2). Is it a VNC or fvwm issue ? Note that connecting a viewer from the old machine to the vnc server on the new one works ok.

[size=85]The menu entry requires an edit (-Shared after the host:display) to work but that is clearly a VNC issue. [/size]

Use FvwmIdent or xprop and check that the class/resource/name matches TigerVNC correctly. That could be the issue.