diff --git a/clientside_validation.js b/clientside_validation.js
index 3cc334f..cf624b9 100644
--- a/clientside_validation.js
+++ b/clientside_validation.js
@@ -1146,8 +1146,18 @@
       var parts = value.split(param.splitter);
       var expectedpartscount = 0;
       var day = parseInt(parts[param.daypos], 10);
+
       var month = parseInt(parts[param.monthpos], 10);
+      if (isNaN(month)) {
+        if (typeof Drupal.settings.clientside_validation_settings[parts[param.monthpos]] !== undefined) {
+          month = Drupal.settings.clientside_validation_settings[parts[param.monthpos]];
+        }
+        else {
+          month = new Date(parts[param.monthpos] + " 1, 2000");
+          month = month.getMonth();
+      }
       month = month - 1;
+
       var year = parseInt(parts[param.yearpos], 10);
       var date = new Date();
       var result = true;
@@ -1293,4 +1303,4 @@
     }
   };
 
-})(jQuery);
\ No newline at end of file
+})(jQuery);
diff --git a/clientside_validation.module b/clientside_validation.module
index 13e8e8d..8ed305c 100644
--- a/clientside_validation.module
+++ b/clientside_validation.module
@@ -38,6 +38,14 @@ function clientside_validation_js_alter() {
       }
     }
   }
+
+  // Provide conversion table between translated month names, both full and abbreviated, and their number.
+  foreach (range(1, 12) as $month_number) {
+    $date = mktime(12, 0, 0, $month_number, 1, 1970);
+    $clientside_validation_settings['clientside_validation_settings']['months'][t(date('F', $date))] = $month_number;
+    $clientside_validation_settings['clientside_validation_settings']['months'][t(date('M', $date))] = $month_number;
+  }
+
   drupal_add_js($clientside_validation_settings, 'setting');
 
 }
@@ -1555,7 +1563,7 @@ function clientside_validation_library_alter(&$libraries, $module) {
     }
 
     $path = drupal_get_path('module', 'clientside_validation');
-    
+
     // Replace jQuery Form plugin.
     $libraries['jquery.form']['js']['misc/jquery.form.js']['data'] = $path . '/jquery.form.js';
     $libraries['jquery.form']['version'] = '3.09';