Yeah...sorry CarolineBogart - wish it worked but two things:

unlike jodpcc I still got the out of stock warning next to the original our of stock product....but no warning at all for the additional out of stock products I put in the cart.

when I put the old header_php back, everything was fine.

(had some down time so went for it...wouldn't hurt to play with this idea a bit more, if only the code writer for this version of the mod would comment)