fix buglet

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@8200 d0543943-73ff-0310-b7d9-9358b9ac24b2

src/include/switch_cpp.h

@@ -148,7 +148,7 @@ class CoreSession {
 
 	int answer();
 	int preAnswer();
-	virtual void hangup(char *cause);
+	virtual void hangup(char *cause = "normal_clearing");
 	void setVariable(char *var, char *val);
 	const char *getVariable(char *var);