Based on your javac command line and output, it looks as though you are referencing kvclient.jar incorrectly. I believe the path to the file should be ../lib/kvclient.jar.
Also, depending on what version of NoSQL DB you downloaded, there might not be a kvclient.jar file present. It might have a version number suffix (e.g. kvclient-2.0.23.jar). If so, either update your classpath to reflect that name change or create a symlink to the versioned jar file from kvclient.jar.