You seem to have two problems in my mind: (a) multiple countries; and, (b) Blackberry. Data is always more expensive when you cross borders. Vodafone's Data Passport is your best bet, but 3gigs of data is a lot. Their plans make out at roughly 300 megs for about 175EUR (depending on the country). iPhone Trip could be an option. I believe that they can turn Blackberry functions on as needed:
Benefits of using iPhoneTrip - 3G Internet SIM for 200+ countries, 1Gb to unlimited roaming data plans, 24/7 support