Anyone else have this problem roaming out west with Verizon?

In December 2001, I traveled to Phoenix and eventually to Las Vegas due to a layover. My Verizon Wireless 5185i would receive calls, make and recieve emails(SMS's too), make local calls but NOT long distance calls back to home. Well, that P*iss*d me off of course! It was a waste to bring it. When I dialed 1-302-XXX-XXXX, it would say Verizon cannot connect your call, and I tried without the 1 too. I called customer service, they had no idea why I couldn't make long distance calls. Can anyone explain this?! I am a Freeup prepay customer, but that shouldn't matter, I was in Freeup area. (I frequently roam in MD, and make LD calls fine there.) I will be going out to San Francisco, and Las Vegas in June, and I want to know if my phone will work. It is really stupid that VZ doesn't know why the network wouldn't let me make LD calls. VZ service is great at home at least.