diff --git a/irc/client.go b/irc/client.go
index bd23cf03..983b36bf 100644
--- a/irc/client.go
+++ b/irc/client.go
@@ -535,10 +535,14 @@ func (client *Client) SendFromClient(msgid string, from *Client, tags *map[strin
 }
 
 var (
-	// these are all the output commands that MUST have their last param be a trailing
+	// these are all the output commands that MUST have their last param be a trailing.
+	// this is needed because silly clients like to treat trailing as separate from the
+	// other params in messages.
 	commandsThatMustUseTrailing = map[string]bool{
 		"PRIVMSG": true,
 		"NOTICE":  true,
+
+		RPL_WHOISCHANNELS: true,
 	}
 )
 
diff --git a/irc/server.go b/irc/server.go
index 41ca180a..b404b153 100644
--- a/irc/server.go
+++ b/irc/server.go
@@ -1093,8 +1093,7 @@ func (client *Client) getWhoisOf(target *Client) {
 
 	whoischannels := client.WhoisChannelsNames(target)
 	if whoischannels != nil {
-		// the dodgy +" " hack here is to work around some silly clients that don't parse trailing params correctly. This forces last param to be a trailing always.
-		client.Send(nil, client.server.name, RPL_WHOISCHANNELS, client.nick, target.nick, strings.Join(whoischannels, " ")+" ")
+		client.Send(nil, client.server.name, RPL_WHOISCHANNELS, client.nick, target.nick, strings.Join(whoischannels, " "))
 	}
 	if target.class != nil {
 		client.Send(nil, client.server.name, RPL_WHOISOPERATOR, client.nick, target.nick, target.whoisLine)