Timer allows you to define a clock giving the local world time. (Multiple worlds supported since v0.3)

To define a clock, just place a vertical square of 9x9 blocks of the predefined material and place a lever on the extreem right lower block.
Once the square is recognized by the plugin as a clock, the server warns you with the message "Timer created".
To start or stop the clock, just use the lever, the following messages will be warned : "Timer started" or "Timer stopped".
To remove a clock, just break the lever and the server will warn you with the message "Timer deleted".

If you're not using the Permissions plugin, Timer use the built-in op.non-op system for permissions. Only ops will be able to create a clock.
Otherwise, the Permissions node is: timer.create

This config.yml file contains only 3 lines which define the material ID and Data of the clock's blocks (Default is 42 but blocks like 35:5 are now available too), the material ID and Data of the blocks used for showing time and the 12/24 format.

Just put timer.jar in your server's plugin directory, then restart or reload the server.
You can then modify the configuration file if needed.
Add the Permission node if you use Permissions.