Description:
------------
The purpose of this is to allow an abstract class or an interface to enforce the implementation of a method, without however enforcing the arguments signature.

This is -as I understand it- not a bug, but a feature request.

Reproduce code:
---------------
/***
 * This works in PHP5 but does not anymore in PHP6
 */
class Parnt {
	public function foo() {}
}
class Child extends Parnt {
	public function foo($arg){}
}

/***
 * Those don't work in either 5 or 6
 */
abstract class Abst {
	abstract public function foo();
}
class Child2 extends Abst {
	public function foo($arg){}
}

interface Int {
	public function foo();
}
class Child3 implements Int {
	public function foo($arg){}
}

Expected result:
----------------
/***
 * Proposal for a solution
 */
abstract class AbstFixed {
	abstract public function foo;
}
class Child4 extends AbstFixed {
	public function foo($arg){}
}

// => Declaring the method without parenthesis (which currently throws a parse error) would allow the implementations of this method to use any argument signature they please.

Actual result:
--------------
At the moment those three examples throw a fatal error in PHP6 with : Declaration of Child::foo() must be compatible with that of Parnt::foo()

I don't think it is a bug, but I think having the capability to allow variable function signatures would definitely be a plus, especially with PHP6 coming that prevents the first example to work.