Just to clarify, if you're using the WebViewer wrapper (e.g. new PDFTron.WebViewer(..., viewerElement)), then there is a jQuery version on this page as well as a separate jQuery version on the page of the HTML5 viewer itself. I'm assuming you're referring to the one in the HTML5 viewer (ReaderControl.html) which is currently using 1.8.2 as I've tried using 1.9.1 on the outer page where the wrapper would be located and it seems to work ok.
With that said, we'll add this to the list of features planned for the next version. Generally WebViewer releases happen every 2-3 months, with the last one being 1.7 at the end of December.
PDFTron Systems Inc.