diff --git a/SeedDMS_Core/Core/inc.ClassAttribute.php b/SeedDMS_Core/Core/inc.ClassAttribute.php
index e50662387..e96ae8ed5 100644
--- a/SeedDMS_Core/Core/inc.ClassAttribute.php
+++ b/SeedDMS_Core/Core/inc.ClassAttribute.php
@@ -924,6 +924,7 @@ class SeedDMS_Core_AttributeDefinition { /* {{{ */
 			break;
 		case self::type_email:
 			foreach($values as $value) {
+				$success &= preg_match('/^[a-z0-9._-]+@+[a-z0-9._-]+\.+[a-z]{2,4}$/i', $value);
 			}
 			if(!$success)
 				$this->_validation_error = 5;