[CentOS] Mock - Problems building Centos5 package on Centos6 - where can I ask for advice ?

Hi.

I am trying to use Mock to rebuild a .src.rpm file I have made for PHP 5.3.8
(for Centos6)

I have managed to install deps fine with mock.

When I try to rebuild the package though I get.

(from build.log)

---------------------------------------------------------------------------------------------------------
+ cat /usr/share/aclocal/libtool.m4 /usr/share/aclocal/ltoptions.m4
/usr/share/aclocal/ltsugar.m4 /usr/share/aclocal/ltversion.m4
/usr/share/aclocal/lt~obsolete.m4
cat: /usr/share/aclocal/ltoptions.m4: No such file or directory
cat: /usr/share/aclocal/ltsugar.m4: No such file or directory
cat: /usr/share/aclocal/ltversion.m4: No such file or directory
cat: /usr/share/aclocal/lt~obsolete.m4: No such file or directory
RPM build errors:
error: Bad exit status from /var/tmp/rpm-tmp.90639 (%build)
    Bad exit status from /var/tmp/rpm-tmp.90639 (%build)
Child returncode was: 1
EXCEPTION: Command failed. See logs for output.
 # ['bash', '--login', '-c', 'rpmbuild -bb --target x86_64 --nodeps
builddir/build/SPECS/php.spec']
Traceback (most recent call last):
  File "/usr/lib/python2.6/site-packages/mock/trace_decorator.py", line 70,
in trace
    result = func(*args, **kw)
  File "/usr/lib/python2.6/site-packages/mock/util.py", line 328, in do
    raise mock.exception.Error, ("Command failed. See logs for output.\n #
%s" % (command,), child.returncode)
Error: Command failed. See logs for output.
 # ['bash', '--login', '-c', 'rpmbuild -bb --target x86_64 --nodeps
builddir/build/SPECS/php.spec']
LEAVE do --> EXCEPTION RAISED
---------------------------------------------------------------------------------------------------------

(I can post the full build.log if needed)

If this is not the correct place to ask about this can someone point me
where I can ask ?

Many regards