-The
-.B \-saslmaxssf
-switch can be used to select the maximum value of the Security Strength Factor.
-This is an integer value and the exact meaning of this value depends on the
-underlying SASL mechanism. A value of 0 disables encryption.
+.PP
+If
+.B nmh
+has been compiled with OAuth support, the
+.B \-sasl
+and
+.B \-saslmech xoauth2
+switches will enable OAuth authentication. The
+.B \-user
+switch must be used, and the
+.I user-name
+must be an email address the user has for the service, which must
+be specified with the
+.B \-authservice
+.I service
+switch. Before using this, the user must authorize nmh by running
+.B mhlogin
+and grant authorization to that account. See the
+.IR mhlogin (1)
+man page for more details.