When do Haste effects start?

[Legildur]

Help please for my PbEM group

A wizard moves his base movement and casts Haste as a standard action. When do the benefits from Haste commence? Immediately? That is, does the caster gets an additional partial action in the same round as casting the spell?

Say he is 5th level, do the benefits cease at the end of his action in the 5th round, or just before his action in the 6th round? (Assuming the duration commences in the round of casting).

Thanks in advance.

 

[AuraSeer]

Haste takes effect immediately. You can move, cast Haste, and then cast another spell (or take another partial action) all in the same turn.

If you're 5th level, and you cast the spell on round 1, the benefits cease immediately before your action on round 6.