diff --git a/app/models/message_gateway.rb b/app/models/message_gateway.rb
index 187a97f0c..a0ad2ca2b 100644
--- a/app/models/message_gateway.rb
+++ b/app/models/message_gateway.rb
@@ -2,7 +2,7 @@ class MessageGateway < ActionMailer::Base
   def receive(email)
     user = get_receiving_user_from_email_address(email)
     return false if user.nil?
-    return false unless check_sender_is_in_mailmap(user, email)
+    return false unless check_sender_is_in_mailmap(user, email.from[0])
 
     context = user.prefs.sms_context
     todo_params = get_todo_params(email)
@@ -90,29 +90,24 @@ def get_receiving_user_from_sms_email(address)
     return user
   end
 
-  def check_sender_is_in_mailmap(user, email)
-    if user.present? && !sender_is_in_mailmap?(user, email)
-      Rails.logger.warn "#{email.from[0]} not found in mailmap for #{user.login}"
+  def check_sender_is_in_mailmap(user, from)
+    if user.present? && SITE_CONFIG['email_dispatch'] == 'to' && !sender_is_in_mailmap?(user, from)
+      Rails.logger.warn "#{from} not found in mailmap for #{user.login}"
       return false
     end
     return true
   end
 
-  def sender_is_in_mailmap?(user, email)
-    if SITE_CONFIG['email_dispatch'] == 'to'
-      if SITE_CONFIG['mailmap'].is_a? Hash
-        # Look for the sender in the map of allowed senders
-        SITE_CONFIG['mailmap'][user.preference.sms_email].include? email.from[0]
-      else
-        # If the config mailmap isn't defined, use the values provided by the users.
-        pref_senders = user.prefs.sms_permitted_senders.split(',').collect(&:strip)
-        pref_senders.include? email.from[0]
-      end
-    else
-      # We can't check the map if it's not defined, or if the lookup is the
-      # wrong way round, so just allow it
-      true
+  def sender_is_in_mailmap?(user, from)
+    if SITE_CONFIG['mailmap'].is_a? Hash
+      # Look for the sender in the map of allowed senders
+      SITE_CONFIG['mailmap'][user.preference.sms_email].include? from
+    elif !(pref_senders = user.prefs.sms_permitted_senders).empty?
+      # If the config mailmap isn't defined, use the values provided by the users.
+      pref_senders.split(',').collect(&:strip).include? from
     end
+    # We can't check the map if it's not defined so just allow it
+    true
   end
 
   def get_text_or_nil(text)
diff --git a/app/models/preference.rb b/app/models/preference.rb
index 8e3d23ad9..f7cd7405f 100644
--- a/app/models/preference.rb
+++ b/app/models/preference.rb
@@ -2,7 +2,7 @@ class Preference < ApplicationRecord
   belongs_to :user
   belongs_to :sms_context, :class_name => 'Context'
 
-  validates_uniqueness_of :sms_email, :case_sensitive => false
+  validates :sms_email, uniqueness: { case_sensitive: false }
 
   def self.themes
     { :black => 'black', :light_blue => 'light_blue' }
diff --git a/bin/rails b/bin/rails
index 9d8f5bd1c..f5cab3d60 100755
--- a/bin/rails
+++ b/bin/rails
@@ -5,7 +5,7 @@ SCRIPT=$(readlink -f "$0")
 # Absolute path this script is in, thus /home/user/bin
 SCRIPTPATH=$(dirname "$SCRIPT")
 
-if [ -e ../.use-docker -a ! -e /etc/app-env ];
+if [ -e $SCRIPTPATH/../.use-docker -a ! -e /etc/app-env ];
 then
   $SCRIPTPATH/../script/docker-environment $0 "$@"
 else