sIFR for ordered list numbers? PHP alternatives?

I’m incorporating sIFR into a redesign of my weblog. WP lists post comments in an ordered list, and I’d like to keep it that way if possible.

I’d want to have the list ordinals in a large sIFR font, while the comments themselves are in regular browser text. Is this even possible? Could a variant of this method be used?

If there’s no CSS method of doing what I want, can anyone recommend a way to programmatically increment numbers for each comment with PHP?