Mail::Sender supports several authentication protocols, hopefully the one you need to use is among them. Use

 use Mail::Sender;
 print join(', ', Mail::Sender->QueryAuthProtocols('servername')),"\n"
+;
[download]

to get a list of those supported by the server. The ones supported by Mail::Sender are PLAIN, LOGIN, CRAM-MD5 and NTLM.