--- mass_contact.module	Fri Apr 30 18:36:37 2010
+++ mass_contact.module	Thu Dec 23 13:45:04 2010
@@ -1119,7 +1119,7 @@
 
   $boundary_attachment = md5(uniqid(mt_rand()));
   $boundary_html       = md5(uniqid(mt_rand()));
-  $character_set       = (variable_get('mass_contact_character_set', '')) ? variable_get('mass_contact_character_set', '') : 'UTF-8';
+  $character_set       = variable_get('mass_contact_character_set', 'UTF-8');
   $params              = array();
 
   $body_plain          = '';
@@ -1260,7 +1260,20 @@
       $message .= "\n--". $boundary_html ."\n";
       $message .= "Content-Type: text/html; charset=$character_set; format=flowed\n";
       $message .= "Content-Transfer-Encoding: 7bit\n\n";
-      $message .= $body_html;
+      // If HTMLMail module exists, then create a 'dummy' data structure on which
+      // it can operate, explicitly call the mail alter, and then add the resulting
+      // body to the message.
+      if ( module_exists('htmlmail') ) {
+        $htmlmail_message = array(
+          'headers' => array(),
+          'body' => $body_html,
+        );
+        htmlmail_mail_alter($htmlmail_message);
+        $message .= $htmlmail_message['body'];  // use the HTML marked-up message
+      }
+      else {
+        $message .= $body_html;
+      }
     }
   }
   else {
@@ -1602,7 +1615,7 @@
           $file_path  = file_save_data($file_data, $file_dest .'/'. $_FILES['files']['name']['attachment'], FILE_EXISTS_RENAME);
           $file_url   = file_create_url($file_path);
 
-          $node_message = '<hr>Attachment:<br />'. l($_FILES['files']['name']['attachment'], $file_url);
+          $node_message .= '<hr>Attachment:<br />'. l($_FILES['files']['name']['attachment'], $file_url);
         }
 
         // Save the message as a node.
@@ -1808,7 +1821,21 @@
   }
 
   // Invoke hook_mail_alter() to allow all modules to alter the resulting e-mail.
-  drupal_alter('mail', $message);
+  // If HTMLMail module exists, then we've already had it operate on the HTML portion
+  // of the message in the form submit function, and we don't want it operating
+  // on the whole thing.  So, mimic drupal_alter functionality with an HTMLMail
+  // bypass.
+  if ( module_exists('htmlmail') ) {
+    foreach ( module_implements('mail_alter') as $module ) {
+      if ( $module != 'htmlmail' ) {
+        $function = $module . '_mail_alter';
+        call_user_func_array($function, array(&$message));
+      }
+    }
+  }
+  else {
+    drupal_alter('mail', $message);
+  }
 
   // Removed destruction of multipart/mixed e-mails by the (now missing) call below