diff --git a/workflow/engine/classes/class.calendar.php b/workflow/engine/classes/class.calendar.php
index defe5bb5c..98e2960b1 100644
--- a/workflow/engine/classes/class.calendar.php
+++ b/workflow/engine/classes/class.calendar.php
@@ -829,7 +829,7 @@ class calendar extends CalendarDefinition
     			$newDate = $onlyDate;
     			$hoursDuration -= (float)($secondRes/3600);
     		} else {
-    			$newDate = date('Y-m-d H:i:s', strtotime('+' . (((float)$hoursDuration)*3600) . ' seconds', strtotime($newDate)));
+    			$newDate = date('Y-m-d H:i:s', strtotime('+' . round((((float)$hoursDuration)*3600), 5) . ' seconds', strtotime($newDate)));
     			$hoursDuration = 0;
     		}
     	}