diff --git a/manifests/init.pp b/manifests/init.pp
index 244a59c..3181483 100644
--- a/manifests/init.pp
+++ b/manifests/init.pp
@@ -2,31 +2,29 @@ class exim(
   $mailman_domains = [],
   $sysadmin = []
 ) {
-  package { 'exim4-base':
+
+  include exim::params
+
+  package { $::exim::params::package:
     ensure => present,
   }
 
-  package { 'exim4-config':
-    ensure => present,
+  if ($::operatingsystem == 'Redhat') {
+    service { 'postfix':
+      ensure      => stopped
+    }
   }
 
-  package { 'exim4-daemon-light':
-    ensure  => present,
-    require => [
-      Package[exim4-base],
-      Package[exim4-config]
-    ],
-  }
-
-  service { 'exim4':
+  service { 'exim':
     ensure      => running,
+    name        => $::exim::params::service_name,
     hasrestart  => true,
-    subscribe   => File['/etc/exim4/exim4.conf'],
+    subscribe   => File[$::exim::params::config_file],
   }
 
-  file { '/etc/exim4/exim4.conf':
+  file { $::exim::params::config_file:
     ensure  => present,
-    content => template('exim/exim4.conf.erb'),
+    content => template("${module_name}/exim4.conf.erb"),
     group   => 'root',
     mode    => '0444',
     owner   => 'root',
@@ -35,7 +33,7 @@ class exim(
 
   file { '/etc/aliases':
     ensure  => present,
-    content => template('exim/aliases.erb'),
+    content => template("${module_name}/aliases.erb"),
     group   => 'root',
     mode    => '0444',
     owner   => 'root',
diff --git a/manifests/params.pp b/manifests/params.pp
new file mode 100644
index 0000000..13adb1d
--- /dev/null
+++ b/manifests/params.pp
@@ -0,0 +1,23 @@
+# Class: exim::params
+#
+# This class holds parameters that need to be
+# accessed by other classes.
+class exim::params {
+  case $::osfamily {
+    'Redhat': {
+      $package = 'exim'
+      $service_name = 'exim'
+      $config_file = '/etc/exim/exim.conf'
+      $conf_dir = '/etc/exim/'
+    }
+    'Debian', 'Ubuntu': {
+      $package = 'exim4-daemon-light'
+      $service_name = 'exim4'
+      $config_file = '/etc/exim4/exim4.conf'
+      $conf_dir = '/etc/exim4'
+    }
+    default: {
+      fail("Unsupported osfamily: ${::osfamily} The 'exim' module only supports osfamily Ubuntu or Redhat(slaves only).")
+    }
+  }
+}
diff --git a/templates/exim4.conf.erb b/templates/exim4.conf.erb
index 369d8df..6d9965f 100644
--- a/templates/exim4.conf.erb
+++ b/templates/exim4.conf.erb
@@ -37,7 +37,8 @@
 #                                                                          #
 ########### IMPORTANT ########## IMPORTANT ########### IMPORTANT ###########
 
-CONFDIR = /etc/exim4
+CONFDIR = <%= scope.lookupvar('exim::params::conf_dir') %>
+
 
 ######################################################################
 #                    MAIN CONFIGURATION SETTINGS                     #