Generating RDF from PHP: any PEAR tool?

I'm thinking to use PHP for serving XUL files to Mozilla and I wonder if there is any PHP or, more likely, any PEAR class/tool for generating/managing RDF files (beside the obvious way of writing them to the STDOUT with a series of printf). As you probably know, the template engine of XUL is designed to accept SQL query results encapsulated into RDF files and auto-magically display them in a very nice tree/table widget. Hence the need/wish of a RDF tool (for what regards XML/XSLT, I know there are expat and sablotron included into PHP 4.XX). Any suggestion? ------------------------- Alessandro Bottoni