diff --git a/ChangeLog b/ChangeLog
index 3244e1e40e..a9657b6bdd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Fri Nov 30 18:52:56 2012  Koichi Sasada  <ko1@atdot.net>
+
+	* vm_trace.c (tracepoint_disable_m, tracepoint_enable_m):
+	  fix block parameter.
+	  No arugment should be given to a block which is passed
+	  to TracePoint#enable (and disable).
+
 Fri Nov 30 18:23:26 2012  Koichi Sasada  <ko1@atdot.net>
 
 	* thread.c: rename Thread.control_interrupt
diff --git a/vm_trace.c b/vm_trace.c
index 2a9a0ce69d..3d305c68ef 100644
--- a/vm_trace.c
+++ b/vm_trace.c
@@ -974,7 +974,7 @@ tracepoint_enable_m(VALUE tpval)
 
     rb_tracepoint_enable(tpval);
     if (rb_block_given_p()) {
-	return rb_ensure(rb_yield, tpval, rb_tracepoint_disable, tpval);
+	return rb_ensure(rb_yield, Qnil, rb_tracepoint_disable, tpval);
     }
     else {
 	return tpval;
@@ -1007,7 +1007,7 @@ tracepoint_disable_m(VALUE tpval)
 
     rb_tracepoint_disable(tpval);
     if (rb_block_given_p()) {
-	return rb_ensure(rb_yield, tpval, rb_tracepoint_enable, tpval);
+	return rb_ensure(rb_yield, Qnil, rb_tracepoint_enable, tpval);
     }
     else {
 	return tpval;