diff --git a/Dockerfile b/Dockerfile
index 8adf7a1..85fc6c9 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,7 +1,7 @@
 FROM adamant/busybox:libressl
 MAINTAINER Adam Dodman <adam.dodman@gmx.com>
 
-ENV UID=900 GID=900
+ENV SUID=900 SGID=900
 ADD start_pms /usr/sbin/start_pms
 
 WORKDIR /tmp
diff --git a/start_pms b/start_pms
index e278eb6..784b390 100644
--- a/start_pms
+++ b/start_pms
@@ -18,7 +18,7 @@ then
     exit 1
   fi
 fi
-if su-exec $UID:$GID [ ! -w "$PLEX_MEDIA_SERVER_CONFIG_DIR" ]
+if su-exec -e [ ! -w "$PLEX_MEDIA_SERVER_CONFIG_DIR" ]
 then
   echo "ERROR: CANNOT WRITE IN $PLEX_MEDIA_SERVER_CONFIG_DIR, MAKE SURE I HAVE PERMISSION TO DO THAT!"
   exit 2
@@ -44,4 +44,4 @@ fi
 
 tail -F "$PLEX_MEDIA_SERVER_CONFIG_DIR/Logs/Plex Media Server.log" >/proc/1/fd/1 2>/dev/null &
 
-exec su-exec $UID:$GID "$PLEX_MEDIA_SERVER_HOME/Plex Media Server"
+exec su-exec -e "$PLEX_MEDIA_SERVER_HOME/Plex Media Server"