How to release upgrade of Mac sandbox app that also requires a new certificate with extra entitlement keys?
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I have an existing C++ Qt (cute, not quick time) application that needs to be sandboxed and released to Mac App Store.  My app uses midi in, and many devices these days are usb.  So I add the usb entitlement.  In a later release, I find that I need to add the firewire entitlement.  So my certificate changes due to the extra entitlement.  How can users upgrade to the later release, if the certificate has changed?  
