Detecting VML support

Hi, I'm currently trying to port a HTML/SVG based script to
InternetExplorer/VML. So far everything is working fine as long as I assume
that every SVG-incapable browser is InternetExplorer. Obviously I could check
the useragent or use conditional comments, but I always end up detecting the
browser instead of the feature, so should MSIE ever drop VML support, there
would be trouble. Completely unnecessary trouble, as there are fallbacks. Of
course, I could just try to render some VML and see what I get but that's so
bad that I'm ashamed to even think about it.

In case I wasn't clear enough (seemed to me that way after reading my own
post) I need an equivalent t
document.implementation.hasFeature('http://www.w3.org/TR/SVG11/feature#Shape','1.1')