[css3-speech] voice family prohibition of spaces

>From the voice-family property:
"Names of specific voices may be quoted, and indeed must be quoted if any of the words that make up the name does not conform to the syntax rules for identifiers [CSS3SYN]. Any whitespace characters before and after the voice name are ignored. For compatibility with SSML, whitespace characters are not permitted within voice names."

Historically Apple shipped voices with spaces in the names, e.g. Victoria, High Quality. Right now I am not infront of a Mac to check if this is current practice. Also, the rumor mill implies perhaps dozens of new voices in Mac OS X Lion. 

In other words I believe this restriction is SSML was a mistake. 

If we want to stick to this rule, is it within the remit of the CSS spec to suggest replacing spaces with underscores?

E.g given a name Bruce_2 a UA should first try to locate a voice called literally Bruce_2 and then if that fails "Bruce 2". 

Otherwise I think the reality of actual voice names should trump SSML compatibility.