Phonegap 2.4 Android Proguard config
Try replacing the Cordova "keep" settings in your proguard-project.txt with the following line, which should maintain all Cordova classes, fields, and methods, both public and private (and thus reenable deviceready):
-keep class org.apache.cordova.** { *; }
Then you just need to include your class(es) (presumably extending CordovaPlugin, not just Plugin) e.g.
pre-v3:
-keep public class * extends org.apache.cordova.api.CordovaPlugin
v3+:
-keep public class * extends org.apache.cordova.CordovaPlugin