diff --git a/doc/Changelog b/doc/Changelog
index b911310a6..d32d47878 100644
--- a/doc/Changelog
+++ b/doc/Changelog
@@ -1,5 +1,7 @@
 23 April 2018: Wouter
 	- makedist uses bz2 for expat code, instead of tar.gz.
+	- Fix #4092: libunbound: use-caps-for-id lacks colon in
+	  config_set_option.
 
 20 April 2018: Wouter
 	- man page documentation for dns-over-tls forward-addr '#' notation.
diff --git a/util/config_file.c b/util/config_file.c
index 03756128a..20c7627e4 100644
--- a/util/config_file.c
+++ b/util/config_file.c
@@ -509,7 +509,7 @@ int config_set_option(struct config_file* cfg, const char* opt,
 	else S_YNO("harden-below-nxdomain:", harden_below_nxdomain)
 	else S_YNO("harden-referral-path:", harden_referral_path)
 	else S_YNO("harden-algo-downgrade:", harden_algo_downgrade)
-	else S_YNO("use-caps-for-id", use_caps_bits_for_id)
+	else S_YNO("use-caps-for-id:", use_caps_bits_for_id)
 	else S_STRLIST("caps-whitelist:", caps_whitelist)
 	else S_SIZET_OR_ZERO("unwanted-reply-threshold:", unwanted_threshold)
 	else S_STRLIST("private-address:", private_address)