You could build and install the same version of Perl on your system twice. Just when you run Configure to build and install your second version use --prefix=/some/where/else. Then install the module you want to test in both Perl's. Something like 
$ /where/you/put/bin/perl -MCPAN shell
cpan> install NWCLARK/Foo-Bar-0.02.tar.gz
...
$ /some/where/else/bin/perl -MCPAN shell
cpan> install NWCLARK/Foo-Bar-0.01.tar.gz

[download]
Then in your test script just change the shebang.

In reply to Re: Change package name on the fly? by Plankton
in thread Change package name on the fly? by pileofrogs

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