| Subject: | --module=Acme-Foo creates Acme-Foo.pm |
Acme-Foo is not a legal package name (you can't say package Acme-Foo or use Acme-Foo)
and thus shouldn't be allowed.
Legal package names generally conform to
[a-zA-Z_][a-zA-Z_0-9]*(?:::[a-zA-Z_0-9]+)*
RT for rt.cpan.org