[GRASS-user] g.extension_PROBLEM_UBUNTU_10.04

[Matteo Mura]

Hello everybody
i'm using ubuntu 10.04 and i've installed GRASS following the instructions of this page http://grass.osgeo.org/grass64/binary/linux/snapshot/ . I'm trying to install an addon with g.extension but the result is the following message:

(Sat May 14 10:49:23 2011)                                                      
g.extension extension=r.basin svnurl=https://svn.osgeo.org/grass/grass-addons/ prefix=$GISBASE
Fetching <r.basin> from GRASS-Addons SVN (be patient)...
A    r.basin/r.basin1.gif
A    r.basin/r.basin2.gif
A    r.basin/r.basin.py
A    r.basin/description.html
A    r.basin/Makefile
Estratta revisione 46265.
Compiling <r.basin>...
mkdir: impossibile creare la directory "/build": Permesso
negato
mkdir -p /build/buildd/grass-6.4.0/bin.x86_64-pc-linux-gnu
make: *** [/build/buildd/grass-6.4.0/bin.x86_64-pc-linux-
gnu] Errore 1
ERROR: Compilation failed, sorry. Please check above error messages.
(Sat May 14 10:49:32 2011) Comando terminato (9 sec)                            
 
could you help me to solve this problem, please ?

thanks