#1251 Disabling log notification in config causes a fatal error

git-svn-id: http://svn.code.sf.net/p/itop/code/trunk@4163 a333f486-631f-4898-b8df-5754b55c2be0

core/action.class.inc.php

@@ -262,8 +262,10 @@ class ActionEmail extends ActionNotification
 			{
 				$sPrefix = '';
 			}
-			$oLog->Set('message', $sPrefix.$sRes);
-
+			if ($oLog)
+			{
+				$oLog->Set('message', $sPrefix . $sRes);
+			}
 		}
 		catch (Exception $e)
 		{