SYNOPSIS
	void replace_program(string program)

DESCRIPTION
	Substitutes a program with an inherited one. This is useful if
	you consider the performance and memory consumption of the
	driver. A program which doesn't need any additional variables
	and functions (except during creation) can call
	replace_program() to increase the function-cache hit-rate of
	the driver which decreases with the number of programs in the
	system.	 Rooms are a good example for the application of this
	function, as many rooms just consist of an inherit statement
	and the configure function. Any object can call
	replace_program() but looses all extra variables and functions
	which are not defined by the inherited program.