Zend_Reflection_Extension extends
ReflectionExtension, and follows its API. It overrides
the following methods to add an additional argument for specifying
the reflection class to use when fetching a reflection object:
getFunctions($reflectionClass = 'Zend_Reflection_Function'): retrieve an array of reflection objects representing the functions defined by the extension.getClasses($reflectionClass = 'Zend_Reflection_Class'): retrieve an array of reflection objects representing the classes defined by the extension.