Do I need to recompile Apache2 "--with-apxs" for PayPal PHP SDK?

I'm trying to install and configure PayPal Website Payments Pro using the PayPal PHP SDK. The first step in the SDK Quickstart instructions is: Enable Apache modules and APXS (Apache Extension Tool) In your Apache root directory, run: ../configure ?enable-mod=so --with-apxs /usr/local/apache/bin/apxs (sic) I think of the ./configure directive as a precursor to compiling with "make," yet there is no mention made of running "make". I'm running RHEL 4.1 with Apache 2 precompiled. I can see that modules are enabled, but I'm guessing it wasn't compiled with apxs since I just installed apxs 10 minutes ago. (FWIW, it's part of the httpd-devel package.) But, then, when I search the Apache site, I see no mention of a "--with-apxs" directive for Apache 2 (only for Apache 1.3). So I'm thinking the instructions may be a little off. Is there such a directive for Apache 2? So I'm wondering if this step is really necessary. I hate to futz with a perfectly fine Red Hat installation if it isn't. Does anyone know how PayPal uses apxs? Does it actually build its own module to be loaded into apache? If I proceed without recompiling Apache, how will I be able to tell if my existing installation of Apache is inadequate? Any help would be appreciated. Thanks.