diff --git a/plugins/lxc/lxc_ram b/plugins/lxc/lxc_ram
index 004f829a..c0437341 100755
--- a/plugins/lxc/lxc_ram
+++ b/plugins/lxc/lxc_ram
@@ -13,16 +13,16 @@ lxc_ram - Plugin to monitor LXC memory usage.
     user root
 
   [lxc_ram]
-    env.stack_usage true
+    env.areastack true
 
 =head1 INTERPRETATION
 
 This plugin needs root privilege.
 
-If env.stack_usage is set to true, all memory usages of containers will be
+If env.areastack is set to true, all memory usages of containers will be
  drawn as stacked area charts.
 This option changes graph order, all of 'Mem usage' comes first and then others.
-(default: empty)
+(default: false)
 
 =head1 AUTHOR
 
@@ -70,7 +70,7 @@ if [ "$1" = "config" ]; then
  echo 'graph_vlabel byte'
  echo 'graph_category memory'
 
- if [ "$stack_usage" = "true" ]; then
+ if [ "$areastack" = "true" ]; then
   for guest_name in $guest_names; do
     guest="$(clean_fieldname $guest_name)"
 
@@ -84,7 +84,7 @@ if [ "$1" = "config" ]; then
   do
    guest="$(clean_fieldname $guest_name)"
 
-   if [ "$stack_usage" != "true" ]; then
+   if [ "$areastack" != "true" ]; then
     echo 'mem_usage_'$guest'.label '$guest_name': Mem usage'
     echo 'mem_usage_'$guest'.type GAUGE'
    fi