diff --git a/ml.cpp b/ml.cpp
index f02b0d2..0c09547 100644
--- a/ml.cpp
+++ b/ml.cpp
@@ -1954,7 +1954,7 @@ MlValue thread_create(std::vector<MlValue> args, MlEnvironment &env) {
 		    for (size_t i = 0; i < args.size(); i++)
 			    MlValue acc = args[i].eval(env);
 	    } catch (std::exception &e) {
-		    std::cerr << "thread exception: " << e.what() << std::endl;
+		    std::cerr << "thread_create exception: " << e.what() << std::endl;
 		    throw e;
 	    }
 	};
@@ -1974,15 +1974,15 @@ MlValue thread_create(std::vector<MlValue> args, MlEnvironment &env) {
 }
 
 MlValue thread_under_lock(std::vector<MlValue> args, MlEnvironment &env) {
-	if (args.size() != 2)
-		throw MlError(MlValue("thread_under_lock", thread_under_lock), env, args.size() > 2 ? TOO_MANY_ARGS : TOO_FEW_ARGS);
+	if (args.size() < 2)
+		throw MlError(MlValue("thread_under_lock", thread_under_lock), env, TOO_FEW_ARGS);
 
 	if (args[0].as_string() != "ilock")
 		throw MlError(MlValue("thread_under_lock", thread_under_lock), env, UNKNOWN_ERROR);
 
 	std::lock_guard<std::mutex> lockGuard(interpreter_mutex);
 	MlValue acc;
-	for (size_t i = 0; i < args.size(); i++)
+	for (size_t i = 1; i < args.size(); i++)
 		acc = args[i].eval(env);
 
 	return acc;