Here in Nov 2013 I could not use my iPhone4 in Ireland even though I signed up for international calling before I left. Your International pay as you go global calling is a farce. From now on I am sticking to European calling cards. They both cheaper and they work.
Did you even research the plan through the international trip planner on this website? My guess is you just went to change features, saw the international dial feature and added it without checking anything else. Your phone is NOT a global phone. It doesn't work in Ireland, period. It has nothing to do with the plan. Your phone is not GSM, and Ireland is a GSM country. So your phone not working had to do with the phone you purchased not the plan.
The whole wireless industry in this country is a FARCE. Predatory investor-driven corporate capitalism for ever increasing margins quarter over quarter is all that drives it. European infrastructure and business models are far superior to ours. Shared networks under a common HSPA/LTE standards, fairly reasonable prices for service, tethering is seldom blocked or up-charged as "features", and Europeans who blog on other forums laugh their butts off at the absurd prices we pay. And what do we get? SIM-locked, CARRIER-locked, BOOTLOADER-locked phones whose "global"HSPA radios don't work on foreign carriers as the OP remarked. And why is it like that? A gutless lobbyist-quashed FCC, FTC, and DOJ.
I have read elsewhere that because the European system is the way it is, there is little incentive for private investment in the in the infrastructure,but I say fine. It works, it's consumer-friendly, it's interoperable, and if it mans government investments for innovation, well I couldn't think of a better use of European tax dollars. Couldn't imagine a better use of American tax dollars either for that matter, but instead of single-payer health care and nationalized wireless, we prefer to drain our tax dollars away on wars and national surveillance.
I just returned from Ireland and my phone was useless but my girls droid worked great. I am formally from there and call from stateside regularly. I visited isreal 2 years ago and had an lg that worked great. What exactly are you fools at verizon doing in the global village we now reside in, wake up, smell the coffee. I run a business and hated the inadequacies portrayed by verizon and their obvious issues with the apple brand. I dont know why I stay with this ridiculous service conglomerate company, who are you really taking care of. Try listening to your clients even if you do not think they are right.