Just do you spans thus:
<span class=”pullquote pqLeft”> or
<span class=”pullquote pqRight”>
There are also a number of under-the-hood improvements to the code, including laying groundwork for planned text-modification features. I also consolidated the files a bit.
Unfortunately WordPress 2.1 completely broke the button in the rich-text post editor, but you can still add the spans manually. Also there is still a button if the rich-text editor is turned off in your User Options.
Also due to certain conflicts in HTML, I have removed the option to use <p> as a container for the pull-quote. As it is, the container you use (<blockquote> or <div>) itself has a paragraph inside it — just FYI for those fiddling with the styles.