Work around issue 131 by checking for empty handles

src/api.cc

Index: src/api.cc
===================================================================
--- src/api.cc	(revision 615)
+++ src/api.cc	(working copy)
@@ -230,7 +230,13 @@
 
 v8::Handle<Value> ThrowException(v8::Handle<v8::Value> value) {
   if (IsDeadCheck("v8::ThrowException()")) return v8::Handle<Value>();
-  i::Top::ScheduleThrow(*Utils::OpenHandle(*value));
+  // If we're passed an empty handle, we throw an undefined exception
+  // to deal more gracefully with out of memory situations.
+  if (value.IsEmpty()) {
+    i::Top::ScheduleThrow(i::Heap::undefined_value());
+  } else {
+    i::Top::ScheduleThrow(*Utils::OpenHandle(*value));
+  }
   return v8::Undefined();
 }