Solved Mate not starting with message "No GSettings schemas are installed on the system"

Trying to install MATE on 10.3-RELEASE, startx crashes with error message "No GSettings are installed on the system ...".
X starts fine with twm or xfce, but not when I put "exec mate-session" on my .xinitrc.
Mate worked fine with the same hardware on a previous RC of 10.3.
Any advice ?
Actually I am just installing the binaries from the ports (not compiling them) so I thought that those things were automagically set.
I will try to set the GSETTINGS_SCHEMA_DIR and XDG_DATA_DIRS variables to some sensible value (/usr/local/share/gconf/shemas/ ?) before lauching mate.
I couldn't manage to get a correct path but by force-reinstalling gsettings-desktop-schemas I am now able to successfully start mate :
pkg install -f gsettings-desktop-schemas did the work (without redownloading anything, it was already there a part of some dependancies)