ClassNotFoundException Error. Something wrong with Eclipse IDE

ClassNotFoundException Error. Something wrong with Eclipse IDE

It seems something wrong with Eclipse configuration after updating with
android updates. When i want to use any external jar in my project it's
throwing runtime exception. please have a look over logcat.
09-09 11:08:59.605: W/dalvikvm(27652): Exception
Ljava/lang/NoClassDefFoundError; thrown while initializing
Lcom/google/zxing/client/android/CaptureActivity;
09-09 11:08:59.605: W/dalvikvm(27652): Class init failed in newInstance
call (Lcom/androidaz/scanner/ScannerActivity;) 09-09 11:08:59.605:
D/AndroidRuntime(27652): Shutting down VM 09-09 11:08:59.605:
W/dalvikvm(27652): threadid=1: thread exiting with uncaught exception
(group=0x41e292a0) 09-09 11:08:59.610: E/AndroidRuntime(27652): FATAL
EXCEPTION: main 09-09 11:08:59.610: E/AndroidRuntime(27652):
java.lang.ExceptionInInitializerError 09-09 11:08:59.610:
E/AndroidRuntime(27652): at java.lang.Class.newInstanceImpl(Native Method)
09-09 11:08:59.610: E/AndroidRuntime(27652): at
java.lang.Class.newInstance(Class.java:1319) 09-09 11:08:59.610:
E/AndroidRuntime(27652): at
android.app.Instrumentation.newActivity(Instrumentation.java:1057) 09-09
11:08:59.610: E/AndroidRuntime(27652): at
android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2015)
09-09 11:08:59.610: E/AndroidRuntime(27652): at
android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2125)
09-09 11:08:59.610: E/AndroidRuntime(27652): at
android.app.ActivityThread.access$600(ActivityThread.java:140) 09-09
11:08:59.610: E/AndroidRuntime(27652): at
android.app.ActivityThread$H.handleMessage(ActivityThread.java:1227) 09-09
11:08:59.610: E/AndroidRuntime(27652): at
android.os.Handler.dispatchMessage(Handler.java:99) 09-09 11:08:59.610:
E/AndroidRuntime(27652): at android.os.Looper.loop(Looper.java:137) 09-09
11:08:59.610: E/AndroidRuntime(27652): at
android.app.ActivityThread.main(ActivityThread.java:4898) 09-09
11:08:59.610: E/AndroidRuntime(27652): at
java.lang.reflect.Method.invokeNative(Native Method) 09-09 11:08:59.610:
E/AndroidRuntime(27652): at
java.lang.reflect.Method.invoke(Method.java:511) 09-09 11:08:59.610:
E/AndroidRuntime(27652): at
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1006)
09-09 11:08:59.610: E/AndroidRuntime(27652): at
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:773) 09-09
11:08:59.610: E/AndroidRuntime(27652): at
dalvik.system.NativeStart.main(Native Method) 09-09 11:08:59.610:
E/AndroidRuntime(27652): Caused by: java.lang.NoClassDefFoundError:
com.google.zxing.ResultMetadataType 09-09 11:08:59.610:
E/AndroidRuntime(27652): at
com.google.zxing.client.android.CaptureActivity.(CaptureActivity.java:107)
09-09 11:08:59.610: E/AndroidRuntime(27652): ... 15 more
Please help me if i am missing anything. Please share your experience if
any solution.