diff --git a/protobuf-test/src/common/v2/test_reflect.rs b/protobuf-test/src/common/v2/test_reflect.rs
new file mode 100644
index 000000000..a3917e5dc
--- /dev/null
+++ b/protobuf-test/src/common/v2/test_reflect.rs
@@ -0,0 +1,18 @@
+use super::test_reflect_pb::M;
+
+use protobuf::Message;
+
+#[ignore] // TODO
+#[test]
+fn test_get_sub_message_via_reflection() {
+    let mut m = M::new();
+    m.mut_sub_m().set_n(42);
+    assert!(m.has_sub_m());
+
+    let descriptor = m.descriptor().field_by_name("sub_m");
+    assert_eq!("sub_m", descriptor.name());
+
+    let sub_m = descriptor.get_message(&m);
+    assert_eq!("SubM", sub_m.descriptor().full_name());
+    assert_eq!(42, sub_m.descriptor().field_by_name("n").get_i32(sub_m));
+}
diff --git a/protobuf-test/src/common/v2/test_reflect_pb.proto b/protobuf-test/src/common/v2/test_reflect_pb.proto
new file mode 100644
index 000000000..0f3c71696
--- /dev/null
+++ b/protobuf-test/src/common/v2/test_reflect_pb.proto
@@ -0,0 +1,9 @@
+syntax = "proto2";
+
+message M {
+    optional SubM sub_m = 1;
+}
+
+message SubM {
+    optional int32 n = 1;
+}
diff --git a/protobuf/src/reflect/accessor.rs b/protobuf/src/reflect/accessor.rs
index f45c9532d..08e787dc3 100644
--- a/protobuf/src/reflect/accessor.rs
+++ b/protobuf/src/reflect/accessor.rs
@@ -1,5 +1,6 @@
 use std::hash::Hash;
 use std::collections::HashMap;
+use std::fmt;
 
 use core::Message;
 use core::ProtobufEnum;
@@ -156,6 +157,23 @@ enum FieldAccessorFunctions<M> {
     Map(Box<FieldAccessor2<M, ReflectMap>>),
 }
 
+impl<M> fmt::Debug for FieldAccessorFunctions<M> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            &FieldAccessorFunctions::SingularHasGetSet { .. } =>
+                write!(f, "SingularHasGetSet {{ .. }}"),
+            &FieldAccessorFunctions::Simple(..) =>
+                write!(f, "Simple(..)"),
+            &FieldAccessorFunctions::Optional(..) =>
+                write!(f, "Optional(..)"),
+            &FieldAccessorFunctions::Repeated(..) =>
+                write!(f, "Repeated(..)"),
+            &FieldAccessorFunctions::Map(..) =>
+                write!(f, "Map(..)"),
+        }
+    }
+}
+
 
 struct FieldAccessorImpl<M> {
     name: &'static str,
@@ -216,7 +234,7 @@ impl<M : Message + 'static> FieldAccessor for FieldAccessorImpl<M> {
             FieldAccessorFunctions::SingularHasGetSet {
                 get_set: SingularGetSet::Message(ref get), ..
             } => get.get_message(message_down_cast(m)),
-            _ => panic!(),
+            ref fns => panic!("unknown accessor type: {:?}", fns),
         }
     }