[Vala] Dbus properies notifications

[tetete <geraeusch gmx net>]

Hello
Is there a possibility to get notifications of changed dbus server
properties on the client? 
I guess there is some "on board" vala way of doing this.
serverobject.notify.connect( (s,p)=>{print("%s\n",p.name);});
is not working.
The client can read the properties, but without change notifications,
they are far less useful.
I'm using GDBus and vala-0.10.0
K.