mach/yum build environment help

[Zing]

Hello folks,

I'm new to mach (using seth's mach/yum build environment) and I'm
wondering if i setup something not right. i've gotten as far as a
successful build i think but...

./build.sh perl-XML-LibXSLT
Building as i386 on fedora-development-i386-core with branch devel
Making srpm of perl-XML-LibXSLT
Run Mach (Y/n):  Removing 8 packages ... ....
Getting /home/zbuild/build/extras/srpms/perl-XML-LibXSLT-1.57-4.src.rpm ...
Removing 1 packages ... ....
Building source rpm perl-XML-LibXSLT-1.57-4.src.rpm
Installing BuildRequires ......
Rebuilding source rpm perl-XML-LibXSLT-1.57-4.src.rpm .....
Collecting results of build /usr/src/rpm/SRPMS/perl-XML-LibXSLT-1.57-4.src.rpm
Build of perl-XML-LibXSLT-1.57-4 succeeded, results in
/var/tmp/mach/fedora-development-i386-core/perl-XML-LibXSLT-1.57-4
Results: /var/tmp/mach/fedora-development-i386-core/perl-XML-LibXSLT-1.57-4
Build done.

...that perl-XML-LibXSLT directory is empty... is that normal?  

And a second question, I had to change the buildrequires: from
perl(XML::LibXML) >= 1.57 to perl-XML-LibXML >= 1.57 otherwise i get
ERROR: BuildRequires not met. Is this something one just needs to do, or
is it a bug?

thanks,
zing