No initSVGZoomEvent ?

I've looked all throughout the SVG 1.0 and SVG 1.1 specs. After a while, 
I found that to create an SVGZoomEvent, you use the 'SVGZoomEvents' 
string like:

var evt = document.createEvent('SVGZoomEvents');

BUT nowhere in the specs (unless I'm blind) does it mention an 
initSVGZoomEvent. The IDL doesn't specify anything extra for an 
SVGEvent, so initEvent would work for a 
document.createEvent('SVGEvent'), but what about the SVGZoomEvent? The 
specs define 5 extra properies on top of the UIEvent interface. 
Shouldn't there be an initSVGZoomEvent method?

Thanks for any info,
Jason Davis