diff --git a/workflow/engine/classes/class.calendar.php b/workflow/engine/classes/class.calendar.php
index 41397aaf0..defe5bb5c 100755
--- a/workflow/engine/classes/class.calendar.php
+++ b/workflow/engine/classes/class.calendar.php
@@ -390,7 +390,11 @@ class calendar extends CalendarDefinition
     	$log[] = $dataLog;
     	*/
     	$hoursDuration = (float)$duration;
-    	$newDate = $iniDate;
+    	$newDate = $iniDate;
+    	
+    	if ( G::toUpper($formatDuration) == 'MINUTES' ) {
+    		$hoursDuration = $duration / 60;
+    	}
 
     	while ($hoursDuration > 0) {
     		//$dataLog = array();