Mantis#1447. Thank you kindly, Kinoc for a patch that:

llKey2Name fix to show avatar name instead of "Basic Entity"
One line fix. Replaces "presence.Name" => 
"presence.ControllingClient.Name" to return avatar's name.

OpenSim/Region/ScriptEngine/Common/LSL_BuiltIn_Commands.cs

@@ -3692,12 +3692,13 @@ namespace OpenSim.Region.ScriptEngine.Common
             if (LLUUID.TryParse(id,out key))
             {
                 ScenePresence presence = World.GetScenePresence(key);
-
+                
                 if (presence != null)
                 {
-                    return presence.Name;
+                    return presence.ControllingClient.Name;
+                    //return presence.Name;
                 }
-
+                
                 if (World.GetSceneObjectPart(key) != null)
                 {
                     return World.GetSceneObjectPart(key).Name;