diff --git a/src/java_lang_System.cc b/src/java_lang_System.cc
index d8e8a5a..45a2aee 100644
--- a/src/java_lang_System.cc
+++ b/src/java_lang_System.cc
@@ -111,6 +111,7 @@
 }
 
 void System_arraycopy(JNIEnv* env, jclass, jobject javaSrc, jint srcPos, jobject javaDst, jint dstPos, jint length) {
+  ScopedThreadStateChange tsc(Thread::Current(), Thread::kRunnable);
   Thread* self = Thread::Current();
 
   // Null pointer checks.