Any way to lock out certain combinations in Attributes?

I run a clothing store using ZenCart! 1.3.9h, and would like to know if there is any way to lock out certain combinations in the Product Attributes? For example, I have clothing items which come in colours Black, Brown and Grey and sizes M, L and XL. If I sell out of Black in size L, there doesn't seem to be any way to lock out that particular combination; I can't remove the colour or size, as I still have other stock which needs those values. So far, I have had to add comments in bold beside the relevant item, declaring (NB Black in size L currently out of stock) but customers either don't read, or ignore the comment and order it anyway! Then I have to faff about doing refunds and e-mailing customers to ask for alternative selections, which is a pain. :(

Anyone got any ideas?

There's this:

http://www.zen-cart.com/index.php?main_page=product_contrib_info&products_id=310

I haven't used it.

You can't associate attributes with each other in Zencart though, so unless a Black / Small is a separate attribute, you won't be able to treat it as one.