diff --git a/inc/inc.ClassExtensionMgr.php b/inc/inc.ClassExtensionMgr.php
index 7fc372905..e83b2f928 100644
--- a/inc/inc.ClassExtensionMgr.php
+++ b/inc/inc.ClassExtensionMgr.php
@@ -675,6 +675,9 @@ $EXT_CONF = '.var_export($EXT_CONF, true).';');
 	/**
 	 * Import list of extension from repository
 	 *
+	 * Will also update the list in the cache, which is used by getExtensionList()
+	 * and getExtensionListByName().
+	 *
 	 * @param boolean $force force download even if file already exists
 	 */
 	public function updateExtensionList($version='', $force=false) { /* {{{ */