My mistake. Yeah, regardless, it should be made double digit.
Sure, only colours 10 through 15 will require two digits, and someone could argue that 0 through 9 save bytes (especially since IRC servers limit how much you can put on a line), but I feel standards are important.
It would be as simple as this for other IRC clients. If two numerical digits follow character-3, that is a colour. If a comma follows those numbers, then the two numerical digits following the comma is the background colour.
On another note, another idea would be to have numbers 16 through 95 be used for shades. For example, since 4, 20, 36, 52, 68, and 84 are all the colour red, then 20 ... 84 would be shades of red. 20, 36, and 52 would be progressively darker than 4, and 68 and 84 would be progressively lighter than 4.
