Add or create tag icons

[Dianne Reuby <pramclub yahoo co uk>]

I'm running f-spot 0.4.3.1 on Ubuntu 8.04

Is there a way of adding extra icons to the tag icon manager? I'd like
to use an icon (rather than one of the photo thumbnails) for my "year
taken" tags, but there isn't one that I want to use.

I've been trying to find out what filetypes the icons are, where they
are stored, etc but I must be searching in the wrong place.

TIA

Dianne