diff --git a/doc/gpg.texi b/doc/gpg.texi
--- a/doc/gpg.texi
+++ b/doc/gpg.texi
@@ -1536,7 +1536,9 @@
 
 Note that if the option @option{use-keyboxd} is enabled in
 @file{common.conf}, no keyrings are used at all and keys are all
-maintained by the keyboxd process in its own database.
+maintained by the keyboxd process in its own database. You can override
+that option by prefixing the keyring filename with either a
+@option{gnupg-ring:} or a @option{gnupg-kbx:} respectively.
 
 @item --primary-keyring @var{file}
 @opindex primary-keyring