Centering Tick Labels BETWEEN Tick Marks

I would like to create a plot axis with major tick labels centered between major tick markers instead below tick markers. If you are viewing this email with a fixed-width font, it might look something like:

___.___.___.___|___.___.___.___|___.___.___.___|
LABEL01 LABEL02 LABEL03

Ideally and ambitiously I would like both minor and major labels to be displayed stacked and boxed like:

___.___.___.___|___.___.___.___|___.___.___.___|

1|2|3|4|1|2|3|4|1|2|3|4|
LABEL01|LABEL02|LABEL03|

I’ve been poking around a bit through the examples, the mailing list and the source code, but haven’t quite figured out how to carry out this customization. So far, I have created my own Locator and Formatter, but I have yet to figure out where I can calculate the label locations or put boxes around them.

Your thoughts appreciated,
Alex