Crashing on small number of Android Devices (can't load mono)

Our Unity Android app is out and works just fine on most Android devices (the 6 or so I tested on personally, plus hundreds of customers so far). But a handful of devices have the app crashing on start up. This is what they are getting (via Google Play):

 java.lang.UnsatisfiedLinkError: Couldn't load mono: findLibrary returned null
 at java.lang.Runtime.loadLibrary(Runtime.java:429)
 at java.lang.System.loadLibrary(System.java:554)
 at com.unity3d.player.UnityPlayer.<init>(Unknown Source)
 at com.unity3d.player.UnityPlayerNativeActivity.onCreate(Unknown Source)
 at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
 at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1623)
 at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1675)
 at android.app.ActivityThread.access$1500(ActivityThread.java:121)
 at android.app.ActivityThread$H.handleMessage(ActivityThread.java:943)
 at android.os.Handler.dispatchMessage(Handler.java:99)
 at android.os.Looper.loop(Looper.java:130)
 at android.app.ActivityThread.main(ActivityThread.java:3701)
 at java.lang.reflect.Method.invokeNative(Native Method)
 at java.lang.reflect.Method.invoke(Method.java:507)
 at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866)
 at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:624)
 at dalvik.system.NativeStart.main(Native Method)

This error was from a Sony Ericsson Xperia Neo MT15i device, but I know there's at least one other. Any idea what would cause the error of failing to find mono? Any ideas how we might fix?