An official fix for this security vulnerability is now available in the latest versions of Adobe Reader. Those using any previous version of Adobe Reader should update to new version.
Here is a vulnerability fixing tool for previous version (8.1) of Adobe Reader and Adobe Acrobat.
PDF MailTo Vulnerability Fix Tool from Javacool Software allows you to easily enable the workaround suggested in the Adobe Security Advisory and help secure your system. It also allows you to easily confirm the status of the workaround.
(However it is recommended to download and install the latest version of Adobe Reader. This tool will available for legacy purposes).