I am creating CEA-608/708 pop-on closed captions with Sony Vegas Pro 10.0e.

Amongst plain text, I would like to italicize some words. I have no problem doing that.

But in many cases I would like to immediately follow the italics with a plain-text comma or period. Unfortunately Vegas does not seem to allow that. In fact, in its preview window, it always renders a space when there is a change of text format with no space between (not just after italics).

I don't know if this behaviour is by design or a bug, and I cannot test it as I do not have a TV with an ATSC tuner.

Is it possible/"legal"/advisable in closed captions to immediately follow italics with plain-text punctuation?