diff --git a/ChangeLog b/ChangeLog
index 105d532c96..472112a4b1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sat Dec 29 14:06:00 2012  Zachary Scott  <zachary@zacharyscott.net>
+
+	* iseq.c (rb_iseq_line_trace_all, rb_iseq_line_trace_specify): Add
+	  rdoc for experimental C level api of iseq, from r38076
+
 Sat Dec 29 11:37:36 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* object.c (rb_obj_clone): attach clone to its singleton class during
diff --git a/iseq.c b/iseq.c
index 2394691731..b95451e48d 100644
--- a/iseq.c
+++ b/iseq.c
@@ -1981,6 +1981,11 @@ collect_trace(int line, rb_event_flag_t *events_ptr, void *ptr)
     return 1;
 }
 
+/*
+ * <b>Experimental MRI specific feature, only available as C level api.</b>
+ *
+ * Returns all +specified_line+ events.
+ */
 VALUE
 rb_iseq_line_trace_all(VALUE iseqval)
 {
@@ -2016,6 +2021,18 @@ line_trace_specify(int line, rb_event_flag_t *events_ptr, void *ptr)
     }
 }
 
+/*
+ * <b>Experimental MRI specific feature, only available as C level api.</b>
+ *
+ * Set a +specified_line+ event at the given line position, if the +set+
+ * parameter is +true+.
+ *
+ * This method is useful for building a debugger breakpoint at a specific line.
+ *
+ * A TypeError is raised if +set+ is not boolean.
+ *
+ * If +pos+ is a negative integer a TypeError exception is raised.
+ */
 VALUE
 rb_iseq_line_trace_specify(VALUE iseqval, VALUE pos, VALUE set)
 {