daemon.go | 1 +

diff --git a/daemon.go b/daemon.go
index f1c7aac1b2746008330cdba124c7ad715c98b3b0e8b6ffc6c669c4deb9fbb293..cd6a484352ff99a15dc5af3eced4a428450149f5c466cbd33ff863319295d7ae 100644
--- a/daemon.go
+++ b/daemon.go
@@ -162,6 +162,7 @@ 		}
 		nickname := cols[1]
 		// Compatibility with some clients prepending colons to nickname
 		nickname = strings.TrimPrefix(nickname, ":")
+		nickname = strings.ToLower(nickname)
 		for existingClient := range clients {
 			if *existingClient.nickname == nickname {
 				client.ReplyParts("433", "*", nickname, "Nickname is already in use")