I just tried with Strawberry, and it also does not issue a warning. It must be a Windows problem. I'll ping their maintainers.

I hope my other information was useful for you though.

ActiveState knows. They intentionally castrated deprecate to silence the warning.

package deprecate;
use strict;
use warnings;
our $VERSION = 0.01;

# our %Config can ignore %Config::Config, e.g. for testing
our %Config;
unless (%Config) { require Config; *Config = \%Config::Config; }

sub __import {  # disarmed in ActivePerl
...
[download]

Reinstalling deprecate should reactivate the warning. Seeing how it's not dual-lived, the easiest way to do this would be to edit the file to change «sub __import {  # disarmed in ActivePerl» back to «sub import {».

Update: Fixed module name. Added last sentence.