Overall, this module seems to work OK. It does work with IE if the Windows security settings are correct, and it works with Firefox and Safari as the previous reviewer mentioned. The code is a bit messy, and I found a few of the author's assumptions to be incorrect (especially regarding the need for serialization of SMB authentication requests), but it provided a good starting point for a bit of customization.
Also strange, and slightly confusing, is the inclusion of an alternate version of Authen::Smb required by Authen::NTLM. It might be good to document the reason this is needed, and possibly change the name so it doesn't conflict with the *official* version of Authen::Smb.