diff --git a/modules/corelib/string.lua b/modules/corelib/string.lua
index c3627dce..88bd869a 100644
--- a/modules/corelib/string.lua
+++ b/modules/corelib/string.lua
@@ -20,6 +20,10 @@ function string:starts(start)
   return string.sub(self, 1, #start) == start
 end
 
+function string.ends(s, test)
+   return test =='' or string.sub(s,-string.len(test)) == test
+end
+
 function string:trim()
   return string.match(self, '^%s*(.*%S)') or ''
 end
diff --git a/modules/gamelib/game.lua b/modules/gamelib/game.lua
index 401a01e7..809a935f 100644
--- a/modules/gamelib/game.lua
+++ b/modules/gamelib/game.lua
@@ -10,7 +10,7 @@ function g_game.isCreatureNameFormatEnabled()
 end
 
 function g_game.chooseRsa(host)
-  if host:match('.*\.tibia\.com') or host:match('.*\.cipsoft\.com') then
+  if string.ends(host, '.tibia.com') or string.ends(host, '.cipsoft.com') then
     g_game.setRsa(CIPSOFT_RSA)
   else
     g_game.setRsa(OTSERV_RSA)