Well, title tells my problem..
Which iPad do you have?
I've got the first generation of the iPad. The mirroring option also doesn't show up on my iPhone 4.
Then that is normal. You need an iPad 2 (or later) and iPhone 4S (or later) in order to mirror, which is explained in the link along with instructions on enabling mirroring on a compatible device.
Oh, I think I skipped that part. Well thanks anyway, seems like I am going to buy a new iPad.
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