Is it a subrequest, a redirect or a fast redirect?

[Bill Stoddard]

mod_expires (with my latest patch ) is still broken.  The expires header 
will not be added when the resource is resolved via a DirectoryIndex 
(ie, a fast redirect) . mod_expires will not add the expires filter to 
what it believes to be a subrequest and a simple check of (r->main != 
NULL) is not granular enough to tell of a request is a subrequest or a 
redirect/fast-redirect.   I am not about to suggest that redirects 
should inherit the filter stack of the main request :-). An alternate 
solution is to add a flag to request_rec (or some other indicator) that 
a module can check to determine if a request is a true subrequest or a 
redirect (fast or normal).   Perhaps set the flag in make_sub_req based 
on the 'next_filter' argument.  Any other ideas?

Bill