I do not believe you'll be able to update JQuery manually as we likely require specific versions in 15. I recommend upgrading the SmarterMail environment to our latest release, which should include up to date versions of our components. If you need any help getting prepped for the upgrade please don't hesitate to submit a ticket with us as we'd be happy to guide you. Have a good one!
Kyle Kerst
IT Coordinator
SmarterTools Inc.
www.smartertools.com