Is there a chance you don't know PL/pgSQL that well, either?
Not being funny here. Is "RETURN OPAQUE" their way of returning a result set? The docs don't seem very clear, and I don't have a working installation handy right now to test it.
We have to fight the terrorists as if there were no rules and preserve our open society as if there were no terrorists. -- [link|http://www.nytimes.com/2001/04/05/opinion/BIO-FRIEDMAN.html|Thomas Friedman]