TreeView - set border on individual cells

[Mike Martin <redtux1 gmail com>]

Is this possible?

I did originally plan to have certain cells have a background colour to
emphasize that there is a value to change. However as soon as the row is
selected this is all wiped out by the highlight from selected row

So is it possible to set the borders on a cell by cell basis, all I can
find is overall properties for the trreview

Mike