Scope with content source rule

I’am creating a feature that setups  the search settings for a project. The feature creates some content sources and scopes. I discoverd that there is no method for adding a rule type ‘Content Source’ on the Scope.  The following create rule methods are availble:

• CreateAllContetRyle
• CreatePropertyQueryRule
• CreateUrlRule

I expected a method like ‘CreateContentSourceRule’, like the user interface offers. Using reflector I dissabled the page page and found out that a new Content Source rule is created using the CreatePropertyQueryRule:

scope.Rules.CreatePropertyQueryRule(ScopeRuleFilterBehavior.Invlude, managedProperties.[“ContentSource”], “yourconcentsourcename”);