I am also getting error msg saying "unable to connect to iTunes". What I have tried are:
1) reset my iTunes password - did not work
2) logout and log back in - did not work
3) delete app and reinstall - did not work
4) sign out and then try to buy in app forcing me to relog into iTunes - did not work
5) enabled and then disable restrictions in settings - did not work
the apps in questions are "Hero Academy" and "Tiny Farm" to name just 2 apps. I have randomly downloaded a new app which works and I can download any app from iTunes store... so i downloaded "Monster Life" and when I tried to buy in app purchases, IT WORKS.
Basically, I am thinking that all apps prior to today which I have bought I cannot make any in-app purchases, but apps downloaded from today, I am able to make in app purchases...
This is WACKED !!!!
I have emailed iTunes support and no reply yet.
Anyone have any solutions or work arounds, please let me know.