Android ListView crashes while scrolling

i see a weird bug here.. i have a list view which is populated from the server in an async... it populates first and then displays the list view... but when i scroll down it crashes... from the logs i see it is not related to population of list view and all.. ... can you please help me?

04-12 12:39:54.676: E/AndroidRuntime(1984): FATAL EXCEPTION: main
 04-12 12:39:54.676: E/AndroidRuntime(1984): java.lang.NullPointerException
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.widget.AbsListView.obtainView(AbsListView.java:1304)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.widget.ListView.makeAndAddView(ListView.java:1727)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.widget.ListView.fillUp(ListView.java:682)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.widget.ListView.correctTooHigh(ListView.java:1349)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.widget.ListView.fillGap(ListView.java:624)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.widget.AbsListView.trackMotionScroll(AbsListView.java:2944)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.widget.AbsListView.onTouchEvent(AbsListView.java:2065)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.widget.ListView.onTouchEvent(ListView.java:3315)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.view.View.dispatchTouchEvent(View.java:3766)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:897)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:936)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:936)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:936)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:936)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:936)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:936)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:1671)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1107)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.app.Activity.dispatchTouchEvent(Activity.java:2086)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1655)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.view.ViewRoot.handleMessage(ViewRoot.java:1785)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.os.Handler.dispatchMessage(Handler.java:99)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.os.Looper.loop(Looper.java:123)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at android.app.ActivityThread.main(ActivityThread.java:4627)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at java.lang.reflect.Method.invokeNative(Native Method)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at java.lang.reflect.Method.invoke(Method.java:521)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:878)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:636)
 04-12 12:39:54.676: E/AndroidRuntime(1984):     at dalvik.system.NativeStart.main(Native Method)
 

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