Field suffix/prefix output empty span

Hi.
Thanks to develop Webform: it's great!

I have to notice only a small bug.
If a textfield has no "suffix", webform generate a empty tag and xhtml validators report an error.

I know that it's a small but, but I think also it's easy to solve: just put an if clause (if suffix variable is empty or not) creating span tag.

Thanks a lot.