You probably need to clean your application's userlib folder of duplicate jar files. This looks like you have several versions of commons-codec.jar.
To clean this, go into your application's userlib folder. Look for .jar files with the same name, but different version numbers. Delete the ones with the lower version numbers, keeping the one with the highest version number.
Clean your deployment directory, and rebuild your application.
I hope this helps and has got your application working, Good luck!