Actionscript Colour Change At Specific Time

hey could someone please tell me how to make an object turn from one colour to another at a specific time?

the reason i need to so this is that i require a few objects to change instantly from one colour to another (e.g. no fading), but at different points in time.

a function that could take a finishing colour value and a time in seconds, for example, would be cool.

thank you!