diff --git a/irc/handlers.go b/irc/handlers.go
index 0883b3b4..2b6c23c6 100644
--- a/irc/handlers.go
+++ b/irc/handlers.go
@@ -2974,7 +2974,7 @@ func registerHandler(server *Server, client *Client, msg ircmsg.Message, rb *Res
 			announcePendingReg(client, rb, accountName)
 		}
 	case errAccountAlreadyRegistered, errAccountAlreadyUnregistered, errAccountMustHoldNick:
-		rb.Add(nil, server.name, "FAIL", "REGISTER", "USERNAME_EXISTS", accountName, client.t("Username is already registered or otherwise unavailable"))
+		rb.Add(nil, server.name, "FAIL", "REGISTER", "ACCOUNT_EXISTS", accountName, client.t("Username is already registered or otherwise unavailable"))
 	case errAccountBadPassphrase:
 		rb.Add(nil, server.name, "FAIL", "REGISTER", "INVALID_PASSWORD", accountName, client.t("Password was invalid"))
 	default:
diff --git a/irc/nickserv.go b/irc/nickserv.go
index 51735be1..c973dc89 100644
--- a/irc/nickserv.go
+++ b/irc/nickserv.go
@@ -1055,10 +1055,10 @@ func nsSaregisterHandler(service *ircService, server *Server, client *Client, co
 		var failCode string
 		if err == errAccountAlreadyRegistered || err == errAccountAlreadyVerified {
 			errMsg = client.t("Account already exists")
-			failCode = "USERNAME_EXISTS"
+			failCode = "ACCOUNT_EXISTS"
 		} else if err == errNameReserved {
 			errMsg = client.t(err.Error())
-			failCode = "USERNAME_EXISTS"
+			failCode = "ACCOUNT_EXISTS"
 		} else if err == errAccountBadPassphrase {
 			errMsg = client.t("Passphrase contains forbidden characters or is otherwise invalid")
 			failCode = "INVALID_PASSWORD"
diff --git a/irctest b/irctest
index e9e37f54..8fc57a55 160000
--- a/irctest
+++ b/irctest
@@ -1 +1 @@
-Subproject commit e9e37f5438bd5f02656b89dab0cd40ef113edac6
+Subproject commit 8fc57a55caa717188129bb7c6399f8143442ed54