Symptoms

After an upgrade of JIRA, the UPM, or a plugin, the following appears in the atlassian-jira.log:

java.lang.NoClassDefFoundError: com/atlassian/jira/datetime/DateTimeFormatterFactory

Cause

The DateTimeFormatterFactory is a new feature found in JIRA 4.4.x. Any components that rely upon that class, or upon a component created by that class, will not be compatible with version 4.3.4 or earlier.

Workaround

To work around this issue, carefully check that each of your plugins is compatible with the JIRA version you're using

Resolution