How can I switch the Play Account used for in-app billing?
No matter which account I "activate" in the Market app, all in-app purchases only go through the first account which is contrary to the experience when purchasing normal apps.
When purchasing normal apps, the billed account is the one that was active in the Market app at the time of purchase.
This causes a problem as I am also unable to restore my in-app purchases unless the account that made the purchases is the primary account on the device.