diff --git a/doc/guix.texi b/doc/guix.texi
index 49d4ef8473..2e5141d3bb 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -20083,6 +20083,15 @@ Defaults to @samp{#f}.
 
 @end deftypevr
 
+@deftypevr {@code{protocol-configuration} parameter} space-separated-string-list managesieve-notify-capabilities
+Which NOTIFY capabilities to report to clients that first connect to
+the ManageSieve service, before authentication.  These may differ from the
+capabilities offered to authenticated users.  If this field is left empty,
+report what the Sieve interpreter supports by default.
+
+Defaults to @samp{()}.
+@end deftypevr
+
 @deftypevr {@code{protocol-configuration} parameter} space-separated-string-list mail-plugins
 Space separated list of plugins to load.
 @end deftypevr
diff --git a/gnu/services/mail.scm b/gnu/services/mail.scm
index b45bf836a9..762662c58c 100644
--- a/gnu/services/mail.scm
+++ b/gnu/services/mail.scm
@@ -364,7 +364,13 @@ (define-configuration protocol-configuration
 and annotations over IMAP.
 
 If this is @samp{#t}, you must also specify a dictionary @i{via} the
-@code{mail-attribute-dict} setting."))
+@code{mail-attribute-dict} setting.")
+  (managesieve-notify-capability
+   (space-separated-string-list '())
+   "Which NOTIFY capabilities to report to clients that first connect to
+the ManageSieve service, before authentication.  These may differ from the
+capabilities offered to authenticated users.  If this field is left empty,
+report what the Sieve interpreter supports by default."))
 
 (define (serialize-protocol-configuration field-name val)
   (format #t "protocol ~a {\n" (protocol-configuration-name val))