Android : com.fasterxml.jackson.databind.ObjectMapper NoClassDefFoundError

this is my first time asking a question so bare with me and im fairly new to software development...

Im working in the Android Eclipse IDE and I keep getting this error

Fatal Exception

java.lang.NoClassDefFoundError: com.fasterxml.jackson.databind.ObjectMapper

     at com.googlecode.jsonrpc4j.JsonRpcHttpClient.<init>

I have added the .jar for the ObjectMapper class that corresponds to the version stated in the pom.xml file, but it has not helped me...

Would I have to have a specific version of the .jar file added to the libraries?

Please Help Thanks in advance

Mark