Need to add "colon dash" before rdf_register_ns

I could not get the rdf_db:rdf_register_ns/2 function of SWI-Prolog's semweb package to work ... getting errors like "No permission to redefine static method ..." etc.

Now I finally figured out one has to add ":-" before the line with the rdf_db:rdf_register_ns predicate, like so:

:- rdf_db:rdf_register_ns(nmr, '').

or ... inside Bioclipse:
swipl.loadPrologCode(":- rdf_db:rdf_register_ns(nmr, '').");