Procedure: Spawn at x y z Entity ENTITYNAME spawns mobs without weapons

When calling the procedure Spawn at x y z Entity ENTITYNAME it will spawn a mob without a weapon. This makes the mob "Skeleton" and "Witherskeleton" useless.

1. Is it possible to spawn mobs with their original weapon?

2. Is it possible to spawn mobs with any weapon?

3. Will there be a procedure in the future that simply does: Spawn at x y z Entity [entityname] with item [itemicon]

Spawning a simple mob like a skeleton with a bow or any entity with a weapon seems to be a core feature, yet I don't know how to do it. Does anyone have a clue?