while I'm still new exactly how APR fits in the whole picture, maybe some of ap_core_translate belongs there, since what seems to be happening is that some OSs get tripped up on valid URIs (and 3.3 of RFC 2396 does seem to indicate that the URI presented is indeed valid).
yes, the URI is indeed valid... however, core's translate name hook has to assume the URI maps directly to a file on disk via DocumentRoot, and APR is able to tell us (on Win32, Netware, etc.) that the resulting filename isn't valid...
