And I'm assuming it installed correctly ...

There's nothing wrong with the code:

c:\test>copy con testModule.pm
#!/usr/bin/perl

package testModule;
use strict;
use warnings;

sub new{
    my $class = shift;
    my $self = {};
    bless $self, $class;
    return $self;
}

sub printSomething{
    return 'Something!';
}

1;
^Z
        1 file(s) copied.

c:\test>copy con testTestModule.pl
#!/usr/bin/perl -w
use strict;
use testModule;

my $ob = new testModule;

print $ob->printSomething;
^Z
        1 file(s) copied.

c:\test>testTestModule.pl
Something!
[download]

Which only leaves an installation error. Wherever it is being installed, it would appear to be somewhere Komodo can find it, but your (default?) Perl installation cannot.