diff --git a/htdocs/propal.class.php b/htdocs/propal.class.php
index de0c9bb3b3a..31fc2bf5dc1 100644
--- a/htdocs/propal.class.php
+++ b/htdocs/propal.class.php
@@ -2000,6 +2000,8 @@ class Propal extends CommonObject
 	 */
 	function verifyNumRef($soc)
 	{
+		global $conf;
+		
 		$sql = "SELECT rowid";
 		$sql.= " FROM ".MAIN_DB_PREFIX."propal";
 		$sql.= " WHERE ref = '".$this->ref."'";