Extraneous request on PATH_INFO url

Hi all,

I'm migrating our web server from Apache1.3/modperl1 to Apache2.2/modperl2.
Everything went smoothly (thanks for the great documentation on
perl.apache.org !), until I began to set up FixurHandlers and
CleanUpHandlers to manage the user session.

At that point, I noticed something strange : when the browser requests a
script with a path_info part, my FixupHandler script traces a request on the
path_info part. e.g. an initial request to
http://myserver.domain.com/perl/script.pl/perl/module generates a request to
/perl/script.pl, but also an inner (sub?) request to /perl/module.  The
subrequest doesn't seem to call the ResponseHandler, it goes straigth from
Fixup to CleanUp.

So I see this:

[MapToStorage] /perl/script.pl/perl/module
[Fixup]  /perl/script.pl
[MapToStorage] /perl/module
[Fixup] /perl/module
[CleanUp] /perl/module
[Response] /perl/script.pl
[CleanUp] /perl/script.pl

It's kinda strange, since /perl/module is just a path_info, but I can live
with that. The problem is that my Fixup handler tries to actually fix things
up for the upcoming request, like tie-ing a variable for my session. When
there's no actual request, I'm tie-ing the variable for nothing, and it's
detrimental.

So I have two questions :

Can I prevent the subrequest ? Maybe a return value to the main Fixup
handler ?
Can I inspect the subrequest to know that it is a subrequest ? Maybe a $r
method ?

Thanks for your time,
Cédric Bertolini