Apologies for the four-group crossposting, but I got responses from
helpful people in all four groups before my December trip to WDW
from California, so I wanted to give a quick report to everyone.

The report is: my Ericsson A2218Z (1900 MHz) phone running on a
Cingular prepaid account from California worked great. I had
allotted time for a trip to the nearest Cingular store the morning
after I arrived, but I didn't need it. I turned the phone on at the
Orlando airport, and it immediately found a signal. I used it a few
times around WDW, and I often didn't get a very strong signal, but
it was usable.

BTW, the login screen said:

310 380

Anyone know what the "310" and "380" mean?

Thanks to all who helped me with this. I hope my information is
of use to others who may be travelling to Orlando with older
(single-band) Cingular prepaid phones.

(followups set to alt.cellular.cingular)

See More: Cingular prepaid at Walt Disney World--followup