Oops: Make sure that the default add-on for SLA computation is enabled by default

git-svn-id: http://svn.code.sf.net/p/itop/code/trunk@1387 a333f486-631f-4898-b8df-5754b55c2be0

modules/itop-sla-computation/model.itop-sla-computation.php

@@ -44,7 +44,7 @@ class SLAComputation
 			throw new CoreException("Could not select this module, '$sModuleName' in not a valid class name");
 			return;
 		}
-		if (!is_subclass_of($sClassName, 'SLAComputationAddOnAPI'))
+		if (($sClassName != 'SLAComputationAddOnAPI') && !is_subclass_of($sClassName, 'SLAComputationAddOnAPI'))
 		{
 			throw new CoreException("Could not select this module, the class '$sClassName' is not derived from SLAComputationAddOnAPI (parent class:".get_parent_class($sClassName)." )");
 			return;