Comment 12 for bug 1268365

While I'm not running Ubuntu, I can confirm that I had saw the same issues with my T440s and it was a matter of the touchpad cable becoming disconnected/connected when the "one button touchpad" is pressed. If you only see the errors when you press the touchpad button, it's fair to say we have the same issue.

You'll need to have the touchpad cable adjusted so that it always stays connected to the touchpad. In the interest of being able to provide further updates on how to fix this issue, please see this Ask Ubuntu answer:
http://askubuntu.com/questions/401072/touchpad-sometimes-not-working-after-click-on-thinkpad-t440s/417135?stw=2#417135