diff --git a/debian/alternc.config b/debian/alternc.config
index c9bd9e27..328bd7cf 100644
--- a/debian/alternc.config
+++ b/debian/alternc.config
@@ -27,6 +27,24 @@ function valid_ip()
 }
 
 
+function get_first_existing_dir() {
+  # Prend en premier parametre un chemin
+  # Retourne le répertoire parent existant le plus "proche"
+  # Exemple: on lui donne /var/www/alternc/gerard/dupont/ mais
+  # seul /var/www/alternc existe, ca répond /var/www/alternc
+  dir="$1"
+  if [ -z "$dir" ] ; then
+    return 0
+  fi
+  if ! test -d "$dir" ; then
+    get_first_existing_dir "$(dirname "$dir")"
+  else
+    echo "$dir"
+  fi
+}
+
+
+
 #checking mysql connectivity and updating local.sh variables accordingly
 check_mysql(){
 
@@ -183,24 +201,28 @@ while [ "$QUEST_STATE" != 0 -a "$QUEST_STATE" != 11 ]; do
 
     db_get alternc/alternc_location
     LOCATION="$RET"
-    #checking acl and quota activation, does't work with NFS yet. should now work with lxc
-    MOUNT_POINT=$(df -P ${LOCATION%/*} | tail -n 1 | awk '{print $6}')
+    #checking acl and quota activation.
+    basedir=`get_first_existing_dir "$LOCATION"`;
+    MOUNT_POINT=$(df -P ${basedir} | tail -n 1 | awk '{print $6}')
+    #we get the first existing dir
+    aclcheckfile="$basedir/test-acl"
+    touch "$aclcheckfile"
+    setfacl -m u:root:rwx "$aclcheckfile" 2>/dev/null
 
-    # Get the mount options for the path: (warning, / may have multiple declarations, take the last one only :
-    MOUNT_OPTS=$(awk '$2=="'$MOUNT_POINT'" { print $4 }' /proc/mounts | tail -1)
-
-    # Check to see if acl is one of the mount points:
-    ACL="$(echo "$MOUNT_OPTS" | tr "," "\\n" | egrep '^acl|attr2|user_xattr$')" || true
-    if [ -z "$ACL" ]; then
+    if [ $? -ne 0 ]; then
+      test -e "$aclcheckfile" && rm -f "$aclcheckfile" || true
       db_input critical alternc/acluninstalled || true
       db_go
       db_reset alternc/acluninstalled || true
       db_fset alternc/acluninstalled "seen" "false" || true
       exit 2
     fi
-    quota_activation=$(quotaon -pa 2>/dev/null |grep '^group.*on$' | /usr/bin/awk '$4 ~ /^\'$MOUNT_POINT'$/ {print $4}') 
-    
-    if [ -z "$quota_activation" -o "$quota_activation"  != "$MOUNT_POINT" ]; then
+    test -e "$aclcheckfile" && rm -f "$aclcheckfile" || true
+
+    quota -gA -f $MOUNT_POINT 2>/dev/null
+
+
+    if [ $? -ne 0 ]; then
         db_get alternc/quotauninstalled
         if [ -z "$RET" ]; then
           db_input critical alternc/quotauninstalled || true