When a required third-party library isn't shipped with an OSGi-compatible manifest, you can use BND to create an updated jar file with the necessary header information. This is documented here
http://www.aqute.biz/Bnd/CommandLine
though some of the options don't seem to actually work.
With a bit of luck though, it may be quicker than manually creating the missing MANIFEST information. The procedure that worked for me is:
cd <path-to-ocs-dist>/lib/bundle
java -jar ../tools/biz.aQute.bnd-3.1.0.jar wrap <path-to-raw-jar-file>