Dividers in Attributes drop down

[mikeyt]

IS there a way to add dividers, or titles, to the Attributes drop down lists?

For example, a current list might look like this (this is a shortened example of what i will be having on my site):

Poster 30x40cm
Poster 40x50cm
Canvas 30x40cm
Canvas 80x100cm
Chunky Canvas 60x80cm
Chunky Canvas 120x200cm

What I would like it to look like would be something like this:

Poster 30x40cm
Poster 40x50cm
------------------
Canvas 30x40cm
Canvas 80x100cm
------------------
Chunky Canvas 60x80cm
Chunky Canvas 120x200cm

Is this possible? Many thanks.
v1.4