I'm unclear on what the behavior you want is. If I have two appointments that overlap, I'd like to know it, even if one is logically at 3pm Pacific and the other is logically at 6pm Eastern.

My usage pattern is that if I need to set up an appointment for a different timezone than my current one, I go over to the timezone menu in the upper right corner of the app, and change my frame of reference to the timezone I need to work in. Then I change it back when I'm done.

If I need to quickly see what the local time for an appointment is, I use the info window, which shows me the time relative to the appointment's timezone. This seems pretty straightforward to me.

That only works if you don't synch with a PalmOS PDA (which doesn't have anywhere to store a timezone).

I want to enter appointments in the time that they will be held at, like next week, where I land at Gatwick at 9AM London on Sunday, and fly to Switzerland at 10AM London on Monday and and at 11AM Swiss and then have a lunch at 1PM Swiss, etc. I want to be able to take that view with me on my PDA, so I can flip the lid and see that I depart at 10AM and arrive at 11AM -- I don't care about the timezone that I land in, I want to be able to tell someone in Geneva that I arrive at 11AM, not noon London.