Axis labeling and axis interaction

hi visad users and developers.

first of all i'd like to thank all the people who spent some of their time
to develope such a great tool, which saved me a lot of time - although  have
to spend a small portion of this time to find out how to do the things I
want to do, because the documentation (at least javadoc) is kept really
short ;-)
ok, but now my questions:
- i want to label the x axis of a Gridded2DSet on my own. The samples are
not evenly spaced multiples of the unit one year. I want 0.5 to be labeled
as "6M", 2 as "2Y", and so on.
- secondly i want these labels to be interactive: if the users clicks a
label, i want the corresponding 2D data to be displayed in a seperate 2D

I hope that i explained my problems adequate.

Thanks in advance,