[GRASS-user] Unable to install add-ons on fedora23

[Salim Razzaz]

Dear GRASS users, I have previously had GRASS 70 compiled from sourcecode and was able to install add-ons with g.extension. Few days ago I discovered the rpm of GRASS 7.0.3 so I removed the compiled one and installed the rpm instead with grass-devel, liblas, and liblas-devel. Now I'm trying to install an add-on but this is happening:

g.extension extension=r.vol.dem --verbose
Fetching <r.vol.dem> from GRASS-Addons SVN repository (be patient)...
A    r.vol.dem/main.c
A    r.vol.dem/r_vol_dem_layerup.jpg
A    r.vol.dem/r.vol.dem.html
A    r.vol.dem/chull.c
A    r.vol.dem/globals.h
A    r.vol.dem/r_vol_dem_layerdown.jpg
A    r.vol.dem/macros.h
A    r.vol.dem/Makefile
A    r.vol.dem/chull.h
 U   r.vol.dem
Checked out revision 68319.
Compiling...
ERROR: Please install GRASS development package

As I'm pretty new in both grass and fedora I'm not really sure what do here. grass-devel is surely installed but somehow it is not recognized when running the command. 
Any help is appreciated.
Thanks

Salim Razzaz