First version of USSD4all for PR 1.2 is ready. You would get it if you update USSD-widget. This release allows you to get rid of pop-up messages. You still would be able to make queries through specialized application (qussd, remake of USSD-pad) and through phone application.
P.S. You need to remove USSD-pad. May be you need remove USSD-widget to update it too. It seems, that you need to reboot the phone after installation.