I used to work for Cingular so here are a couple FAQ's. This gets really confusing.
If you have Cingular the Discounted International Plan formerly World Traveler plan is typically the way to go if you leave the US. If your international travel is infrequent, you can turn the feature on and off as needed if you'd like. No penalty. Saves $6.00 bucks a month. Typically this plan saves $0.30 to 0.50 per minite so the $6.00 fee is made up in about 10 minutes. No brainner. However for some reason, CR is not a country that has any discounts. Curacau as most countries do. If you are only going to CR you only need to have international capability. The rate is $2.29 per minute either way. CR is 2.29 a minute and France and Italy are .99. Who knows why.
Here is a link with Cingualr prices for calls from different countries.
http://onlinestorez.cingular.com/travel ... DIR|WC|WCM
One note for Cingular customers the default setting of your phone is no international calls allowed. You must have international turned on while you are in the US. There is no charge for this but you will pay the highest rates unless you have discounted plan turned on before you leave the country.
For new customers Cingular likes to be a dick and not allow any International calls until you have paid your bills for 6 months. One other gottcha from Cingular when roaming on International is you are only permitted to make calls within the country you are in and back to the US. CR to Brazil for instance are not allowed.
Stinky A Verizon Phone will NOT work on Cingular period. Assuming that your contract is up, you can get a great deal on a new Treo when you change to Cingular. Cingular store will have good prices but better deals can be found on the web. Check out
www.wirefly.com. There are others like it but I can attest these guys have great prices, service and are easy to work with and process orders. You can then sell your Verizon phone on EBAY and recoop a couple more bucks.
This applies to voice only. If you want data that is another whole topic, crappy service and very pricey.