Description:
------------
It's not possible to retrieve default value of an SPL method argument with reflectionParameter class.
If we try to do that, an exception was throwed to inform us that it's not possible.
So, i known that it's a known issue (bug 28114), but it's very annoying and i would like to know the reason of this, or if there is a workaround.

Reproduce code:
---------------
<?php

$method = new reflectionMethod('recursiveDirectoryIterator', 'setFlags');

foreach ($method->getParameters() as $parameter)
{
	echo $parameter->getDefaultValue();
}

Expected result:
----------------
Something that it's not an exception.

Actual result:
--------------
PHP Fatal error:  Uncaught exception 'ReflectionException' with message 'Cannot determine default value for internal functions' in /usr/home/fch/tmp/class.php:7
Stack trace:
#0 /usr/home/fch/tmp/class.php(7): ReflectionParameter->getDefaultValue()
#1 {main}
  thrown in /usr/home/fch/tmp/class.php on line 7