Unable to start receiver org.fdroid.fdroid.receiver.PackageUpgradedReceiver

While sending an (unrelated) package via ADB, I got this crash:

8847-8847/org.fdroid.fdroid E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: org.fdroid.fdroid, PID: 8847
    java.lang.RuntimeException: Unable to start receiver org.fdroid.fdroid.receiver.PackageUpgradedReceiver: java.lang.NullPointerException: Attempt to read from field 'int android.content.pm.PackageInfo.versionCode' on a null object reference
            at android.app.ActivityThread.handleReceiver(ActivityThread.java:2647)
            at android.app.ActivityThread.access$1800(ActivityThread.java:154)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1398)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:135)
            at android.app.ActivityThread.main(ActivityThread.java:5291)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:904)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:699)
     Caused by: java.lang.NullPointerException: Attempt to read from field 'int android.content.pm.PackageInfo.versionCode' on a null object reference
            at org.fdroid.fdroid.receiver.PackageUpgradedReceiver.handle(PackageUpgradedReceiver.java:49)
            at org.fdroid.fdroid.receiver.PackageReceiver.onReceive(PackageReceiver.java:54)
            at org.fdroid.fdroid.receiver.PackageUpgradedReceiver.onReceive(PackageUpgradedReceiver.java:36)
            at android.app.ActivityThread.handleReceiver(ActivityThread.java:2640)
            at android.app.ActivityThread.access$1800(ActivityThread.java:154)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1398)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:135)
            at android.app.ActivityThread.main(ActivityThread.java:5291)
            at java.lang.reflect.Method.invoke(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:372)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:904)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:699)

(this may be because I sent the same package twice in a row, before the receiver had time to process the first installation?)