diff --git a/inc/inc.Utils.php b/inc/inc.Utils.php
index 15d43be93..2d8a850f7 100644
--- a/inc/inc.Utils.php
+++ b/inc/inc.Utils.php
@@ -41,12 +41,23 @@ function getConvertDateFormat() { /* {{{ */
 		return 'yyyy-mm-dd';
 } /* }}} */
 
+/**
+ * Return a human readable date string
+ *
+ * This function formats a timestamp according to the date format
+ * settings. If no timestamp is passed the current date is used.
+ * If null or an empty string is passed, then an empty string
+ * is returned. If $timestamp is numeric it will be taken as a unix
+ * timestamp. If $timestamp is a string it will be parѕed with strtotime().
+ */
 function getReadableDate($timestamp=0) { /* {{{ */
 	global $settings;
-	if(!$timestamp)
+	if($timestamp === 0)
 		$timestamp = time();
-	elseif(!is_numeric($timestamp))
+	elseif($timestamp && is_string($timestamp))
 		$timestamp = strtotime($timestamp);
+	elseif(!is_numeric($timestamp))
+		return '';
 	if($settings->_dateformat)
 		return date($settings->_dateformat, $timestamp);
 	else