[RedWingFan]

For now, I've disabled the plugin. When I get time, I may dissect the function and toss out some variables to see how it is working.

(EDIT: Disregard the following...my error...) For the .co.uk and .co.jp domains, I need those as well. I know that the regex for (co\.uk|co\.jp|de|com|ca) should work (syntax looks correct, and the dots are escaped properly), but I wonder how the script is parsing the $associate_id_co_uk and $associate_id_co_jp variable names, as they have one extra set of underscore and characters than the others. I wonder if that's where the problem lies...? That's why I want to look into the function more to see how it is setting the variables, if only for me to understand how it works overall. It's the regular expressions I sometimes get hung up on.