activate GMap after page load

This is more of a usage or maybe documentation question rather than a feature request, but I'm stumped.

I want to load a gmap after a page has loaded and the reader has taken some action to determine which map, if any, to load.

I'm at the point where my xmlrpc thingie gives a valid gmap div and injects it properly into the page, and I can get the proper javascript (jQuery.extend(...)) code to execute.

What isn't happening is the map getting rendered.

I'm guessing there's some sort of initialization procedure that's supposed to run when the page loads, but isn't getting invoked afterwards.

If so, I can't seem to find it or figure this out. Does such a thing exist and/or is it documented anywhere?