Include an early version of android framework JAR in my application APK?
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I have built an Android app that worked fine on Android 2.3.* and 4.0.*. However, after upgrading my device to Jelly Bean (4.1.1), I found my app does not work properly (crashes, ANRs, etc.) any more.

As a temporary workaround, I am wondering if it is possible to pack an earlier version (say Android 2.3) of the Android framework JAR into my APK and force all my code to use classes/APIs in that JAR?

I think including the JAR in my APK should be easier. But I have no idea how I could force my code to use classes/APIs in the JAR during run-time.

I know it is not a decent fix (hacking, package size, legal issue, etc.) even it will work. But I am just curious whether it is feasible.

Any suggestions or hints would be appreciated!