Gaucho:

My experience with this has been a little mixed. Here are the stories (take what you will):

-JK (Spanair) flight intra-Spain booked as "airport pickup" on United.com. Did this twice. Once, the airport folks spent 45 mins trying to figure out how to issue the ticket (ended up just cancelling it, 'cuz they couldn't figure it out). Other time, worked flawlessly. The first (problematic) time, they said they couldn't see the reservation - talked to the helpdesk - couldn't issue the ticket...no other reason given. I suspect the agent(s) had no experience doing ticketing for other airlines, because nothing was different in the 2 bookings.
-Did an "airport pickup" ticket off United.com for a BD flight AMS-LHR. Called UA, and they said I could pickup the tickets from the BD counter at AMS. When I went to the BD counter, they indicated that I could not ticket that there because the fare basis was only valid for ticketing outside of Europe. I fought with them for a while, and then gave up (only to fight another battle around seat assignment).

None of these flights was a codeshare.

In every case, however, I did not get a choice from united.com about which delivery method to use - just like the e-ticket vs. paper ticket thing on the website. My suggestion to you would be the following:

a) Try different United.xxx websites to see if any will give you an "airport pickup" option.
b) Go to the airport waaaaaay before your flight (pref. prior day) to pickup your ticket, and be prepared to wait.
c) Try flights.com - they use agents in different countries to issue tickets - and sell consolidator fares. Also, you can try travelocity.com and have it issued at an agency.

PS - United is an IATA agency, and therefore can issue tix on any airline. Recent calls on this topic, however, have yielded this response: "We can do it, however HQ has asked us not to because the other airlines will cancel our tickets if they're not in connection with a UA itin."

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