One word of warning about looking to do that sort of thing is getting in to eternal loops. With the out of office reply, the first time somebody emails you it sends the reply, but from then on it doesn't send one if they reply to that email.
I was having issues with my out of office assistant for some reason, and so went into the rules wizard and set up an auto reply, then went on holiday. I came back to an un-openable inbox which had over 325,000 new emails. I had an email from an online shop which the reply address is one of those no-reply email addresses, that when you email it, it emails you back telling you not to. But.. every time it did that, my email sent one back too, and so the chain begins
So go to >tools>rules wizard if you still want to go ahead with this.
Cheers
Hog..