JIRA provides the ability to install plugins that contain custom user formats. When you install one in JIRA 4.4.1, it appears under "Administration" > "User Interface" > "Look and Feel", but you don't get the option to select it when editing the settings. In fact, no user formats (including the default) appear on the configuration screen. See the screen shots for details.

To reproduce this:

1. build the jira-reference-plugin included with the 4.4.1 source
2. install it in 4.4.1
3. Navigate to "Administration" > "User Interface" > "Look and Feel". Note that the user formats provided by the reference plugin are all listed.
4. Click "Edit Configuration"
5. Expand the "Customize Colors and Dates" section and scroll down. Note that the user formats do not appear and are not selectable.

I'm not sure if this is a flaw in the reference plugin or JIRA 4.4.1, either way, it needs to be addressed.

The documentation for the plugin module type is also out of date:

https://developer.atlassian.com/display/JIRADEV/User+Format+Plugin+Module

Whatever the correct process is for installing and configuring these, it needs to be reflected in the developer documentation when all is said and done.