EDGE is a software acceleration to GPRS. "Data Connection refused" can be one of two things, either the network is having issues (IE, RIM/Cingular's recent PIN Deactivation issue) or something is wrong with the billing/account. Either way, it has to do with provisioning. Either your Blackberry Data plan is not active, you havn't called the Terms and Conditions line, or some other issue. Also, Your GPRS could be a SIM card issue, take it out, wipe off the metal contacts, and try again. Also, a ALT+CAP+DEL reset should work. If not, your area is currently a migrating GPRS area with limited EDGE coverage. As I said before, EDGE is only a software accelleration to GPRS. There are FEW but some towers are only GPRS and don't have that accelleration.
Hope this helps.