diff --git a/gui.lua b/gui.lua
index f8d20e0..3f3cc97 100644
--- a/gui.lua
+++ b/gui.lua
@@ -702,7 +702,7 @@ function mail.handle_receivefields(player, formname, fields)
 			local recipients = mail.parse_player_list(fields.to)
 			local isNew = true
 			for r_,recipient in ipairs(recipients) do
-				if mail.split(recipient, "@")[1] == "" then -- in case of maillist
+				if recipient:split("@")[1] == "" then -- in case of maillist
 					isNew = false
 				else
 					for c_,contact in ipairs(contacts) do
diff --git a/storage.lua b/storage.lua
index 51c8e6d..195b202 100644
--- a/storage.lua
+++ b/storage.lua
@@ -248,9 +248,9 @@ function mail.addMaillist(maillist, players_string)
 	table.insert(maillists, 1, maillist)
 	if mail.write_json_file(mail.maildir .. "/mail.maillists.json", maillists) then
 		-- add status for players contained in the maillist
-		local players = mail.split(players_string,"\n")
+		local players = player_string:split("\n")
 		for _, player in ipairs(players) do
-			local playerInfo = mail.split(player, " ")
+			local playerInfo = player:split(" ")
 			if minetest.player_exists(playerInfo[1]) then -- avoid blank names
 				mail.addPlayerToMaillist(playerInfo[1], maillist.id, playerInfo[2])
 			end
@@ -275,9 +275,9 @@ function mail.setMaillist(ml_id, updated_maillist, players_string)
 		-- remove all players
 		mail.removePlayersFromMaillist(maillist_id)
 		-- to add those registered in the updated maillist
-		local players = mail.split(players_string,"\n")
+		local players = players_string:split("\n")
 		for _, player in ipairs(players) do
-			local playerInfo = mail.split(player, " ")
+			local playerInfo = player:split(" ")
 			if minetest.player_exists(playerInfo[1]) then -- avoid blank names
 				mail.addPlayerToMaillist(playerInfo[1], maillist_id, playerInfo[2])
 			end
@@ -398,12 +398,12 @@ function mail.deleteMaillist(ml_id)
 end
 
 function mail.extractMaillists(receivers)
-	local globalReceivers = mail.split(receivers,",") -- receivers including maillists
+	local globalReceivers = receivers:split(",") -- receivers including maillists
 	local receivers = {} -- extracted receivers
 	
 	-- extract players from mailing lists
 	for _, receiver in ipairs(globalReceivers) do
-		local receiverInfo = mail.split(receiver, "@") -- @maillist
+		local receiverInfo = receiver:split("@") -- @maillist
 		if receiverInfo[1] == "" and receiverInfo[2] then -- in case of maillist
 			local players_ml = mail.getPlayersInMaillist(mail.getMaillistIdFromName(receiverInfo[2]))
 			if players_ml then