Merge remote branch 'origin/v0.6'

Conflicts:
	Makefile
	lib/_debugger.js

1 files changed, 5 insertions, 1 deletions

diff --git a/lib/child_process.js b/lib/child_process.js
index 8bcfdf74a0..cef093a0b7 100644
--- a/lib/child_process.js
+++ b/lib/child_process.js
@@ -111,7 +111,11 @@ function setupChannel(target, channel) {
   };
 
   target.send = function(message, sendHandle) {
-    if (!target._channel) throw new Error('channel closed');
+    if (typeof message === 'undefined') {
+      throw new TypeError('message cannot be undefined');
+    }
+
+    if (!target._channel) throw new Error("channel closed");
 
     // For overflow protection don't write if channel queue is too deep.
     if (channel.writeQueueSize > 1024 * 1024) {