How can I gift a custom iTunes playlist for a friend?

Apple claims that I can give a custom mix of songs to someone as a gift, but I can’t find any possible way to do that.

Here’s the link: http://www.apple.com/itunes/gifts/

I quote: “Send a song, an album, a TV episode, an entire TV show, or a movie — EVEN GIVE A CUSTOM MIX OF SONGS — to anyone. Buy a gift and iTunes immediately sends an email to your recipient, who just clicks a link. Your gift starts downloading to your recipient’s iTunes library, ready to play or sync to iPod, iPhone, or Apple TV.”

Can anyone help me on this? I tried making an iMix, but iTunes told me, “iMix publishing is currently unavailable. Please try again later.” Suggestions?