This happens when CPAN.pm detects there is a newer version of CPAN.pm living on CPAN, and then goes to install and activate the newer version. I haven't happen that to me for a long time (nowadays it seems there are no updates to CPAN.pm outside of regular perl releases), and in my experience, it first asks whether it should be upgrade. But there might be a configuration switch to do it automatically.

In reply to Re: CPAN "install" redefines bunches of stuff. Should I worry? by Anonymous Monk
in thread CPAN "install" redefines bunches of stuff. Should I worry? by tphyahoo

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