The JeePlug is a general-purpose mini-board which "happens" to be particularly convenient for use with "ports". It's a small 8 x 10 hole prototype board for simple interconnect tasks to components and connectors.

Here is the back side (of an RTC plug), with headers mounted flat:

See http://news.jeelabs.org/tag/jeeplug/ for all weblog posts related to JeePlugs.
Configuration
There is nothing to configure. This board contains no components, only a few wire connections.
Header Pinouts
There are three pairwise connected rows of pads: the outermost two rows (left and right in the above image), and the center rows (underneath the IC in the above image):

If you want to use these plugs in different orientations, please make sure there are no copper traces where you don't want them. These traces are very thin and can be cut with a knife by cutting through the blue solder mask. Use a continuity tester to make sure the connections have really been broken.
Design Info
Dimensions: 20.2 x 26.6 mm
CadSoft EAGLE design files: jlpcb-014.pdf / jlpcb-014.sch / jlpcb-014.brd.