.htaccess Inheritance?

I’m having a weird .htaccess problem on my site that may or may not be WordPress related. Basically, I’m trying to use cruft-free URIs for my permalinks, and completely separate from the blog itself, I’m using .htaccess to drop the www subdomain thus making my site “Class B” as defined by http://no-www.org/ so all of my traffic to http://www.elasticdog.com is silently redirected to http://elasticdog.com
My .htaccess file to drop the www subdomain is located in the root folder of my site, but WordPress is installed under elasticdog.com/wp/ and needs its own .htaccess file in order to get the permalinks working correctly.
I can’t seem to get the two to work together…my redirects work everywhere on my current site, but if I go to http://www.elasticdog.com/wp/ the redirect to drop the subdomain no longer works.
Admittedly, I don’t understand the whole .htaccess file thing too well, and know that I can re-write the rules by having another file in a child directory (as I have done) but do I have to go back and redefine the rules I want to carry over from the parent directory in that file too? I guess I just need help on getting my own .htaccess rules working together with the ones that WP creates. Any help is much appreciated…