CPAN Testers makefile problem

ambs has asked for the wisdom of the Perl Monks concerning the following question:

Hello, friends.

I am receiving a lot of CPAN testers reports with failures with something like:

Output from '/usr/bin/make':

make: Fatal error in reader: Makefile, line 496: Invalid byte sequence
[download]

I think I remember having a similar problem some years ago, but now I can't remember what was the problem.

Any hint?

Thanks,

Alberto Simões