Mail::Box::IMAP4

~ line 68:
if(@types == 1 && $types[0] eq 'AUTO')
-  {   @types = ('CRAM-MD5', ($ntml_installed ? 'NTLM' : ()), 'PLAIN');
+  {
+      undef @types;
+      my @supported = qw(PLAIN CRAM-MD5); # Mail::IMAPClient supported
+      foreach (grep {^AUTH=/o} $imap->capability)
+	  { my ($mechanism) = /^AUTH=(\w+)/o;
+           # This test only loads AUTH types that are common
+           # between Mail::IMAPClient and the IMAP server
+           next unless grep (/^$mechanism$/, @supported);
+    	    push @types, $mechanism;
+         }
   }
+unless (@types)
+    { die "unable to find a supported authentication method\n" };

Something like that?


I have to admit.  I didn't test this directly in the IMAP4.pm module. 
But I've gotten this to work on an external script and I believe it 
provides the right information for you.

Rather than assuming the authentication @types to be CRAM-MD5, NTLM?, 
and PLAIN I ask the IMAP server what it's capalities are for 
Authentication ($imap->capability returns all the AUTH mechanisms 
supported per RFC2060 section 6.1).  This prevents the login process 
from hanging on an unsupport authentication model.  I haven't been able 
to fold in any inquery to Mail::IMAPClient to find out what it's 
capabilities are, I just assumed them in the @supported array.

There may be better methods to doing this and I'm ALWAYS open to 
improvements.  But hopefully this is helpful.