The latest version is 1.6.1 and if you have created anything using the old or older version of Spry then you can update the site by going to:
Site >> Spry Updater
See this picture:
You can also install the update manually by going to:
<http://labs.adobe.com/technologies/spry/> and downloading the latest version. Spry isn't updated as regularly as DW is so the chances are you must have the latest version on your system.