I don't know what configuration options were used when building 5.6.0;
perl -V[:variable] will give you that information.

You should see something like this without any variables:
Summary of my perl5 (revision 5.0 version 6 subversion 0) configuration:
...and then all of the information you would want to know.

I am sure that `Configure` can grab this information itself, read the manuals (INSTALL README etc).

update: Hmmm... Perhaps this should be an option for the Configure script. "Use current configuration settings, prompt only for new questions." When given the path to your current working perl binary.