You have several options, when it comes to requesting the password under windows. In browsing around CPAN while reading your question, I found the following which I think might include functions for requesting a value that is concealed as it is typed. I won't say they will all do what you seek easily, but might prove useful.

• Term::Prompt
• Term::ReadKey
• Term::ReadLine
• Tk
• Win32::GUI
• Win32::Console
• Wx

Hope that helps get you started, at least...