diff --git a/README.md b/README.md
index bff1fa7..34aed19 100644
--- a/README.md
+++ b/README.md
@@ -52,17 +52,21 @@ OR set local storage:
 
 ENVIROMENT VARIABLES (only available with `docker run`)
 
- * `TIMEZONE` - As above, set a zoneinfo timezone, IE `EST5EDT`
+ * `TZ` - As above, set a zoneinfo timezone, IE `EST5EDT`
 
 ## Examples
 
-### Start an instance and set the timezone:
-
 Any of the commands can be run at creation with `docker run` or later with
 `docker exec samba.sh` (as of version 1.3 of docker).
 
+### Setting the Timezone
+
     sudo docker run -p 139:139 -p 445:445 -d dperson/samba -t EST5EDT
 
+OR using `environment variables`
+
+    sudo docker run -e TZ=EST5EDT -p 139:139 -p 445:445 -d dperson/samba
+
 Will get you the same settings as
 
     sudo docker run --name samba -p 139:139 -p 445:445 -d dperson/samba
diff --git a/samba.sh b/samba.sh
index b7cf5b2..d1d13b9 100755
--- a/samba.sh
+++ b/samba.sh
@@ -57,11 +57,15 @@ share() { local share="$1" path="$2" browse=${3:-yes} ro=${4:-yes}\
 # Return: the correct zoneinfo file will be symlinked into place
 timezone() { local timezone="${1:-EST5EDT}"
     [[ -e /usr/share/zoneinfo/$timezone ]] || {
-        echo "ERROR: invalid timezone specified" >&2
+        echo "ERROR: invalid timezone specified: $timezone" >&2
         return
     }
 
-    ln -sf /usr/share/zoneinfo/$timezone /etc/localtime
+    if [[ $(cat /etc/timezone) != $timezone ]]; then
+        echo "$timezone" > /etc/timezone
+        ln -sf /usr/share/zoneinfo/$timezone /etc/localtime
+        dpkg-reconfigure -f noninteractive tzdata
+    fi
 }
 
 ### user: add a user
@@ -120,7 +124,7 @@ while getopts ":hi:t:u:s:" opt; do
 done
 shift $(( OPTIND - 1 ))
 
-[[ "${TIMEZONE:-""}" ]] && timezone "$TIMEZONE"
+[[ "${TZ:-""}" ]] && timezone "$TZ"
 
 if [[ $# -ge 1 && -x $(which $1 2>&-) ]]; then
     exec "$@"