Upgrading from JIRA 3.13 to 3.13.1
Please follow the JIRA general upgrade instructions
Upgrading from JIRA 3.12 and earlier
In addition to the above, please read the Upgrade Guide for every version you are skipping during the upgrade. The complete list of Upgrade Guides is available here.
IMAP message handling produces issues with no description
If your JIRA instance is set up to create issues and/or comments from e-mails that come from an IMAP mail box, you will need to deploy a patch to address a problem with issue creation (as described in JRA-15954). Please deploy the patch file attached to JRA-15954 (instructions for deploying the patch are contained in this comment of JRA-15954).