diff --git a/include/vms/ChangeLog b/include/vms/ChangeLog
index 823520f22..edd78fe0a 100644
--- a/include/vms/ChangeLog
+++ b/include/vms/ChangeLog
@@ -1,3 +1,7 @@
+2010-05-03  Tristan Gingold  <gingold@adacore.com>
+
+	* dmt.h: Improve comments.
+
 2010-04-30  Tristan Gingold  <gingold@adacore.com>
 
 	* lbr.h (struct vms_kbn): New structure.
diff --git a/include/vms/dmt.h b/include/vms/dmt.h
index f2f4e0d5d..f2aad6e99 100644
--- a/include/vms/dmt.h
+++ b/include/vms/dmt.h
@@ -25,10 +25,10 @@
 
 struct vms_dmt_header
 {
-  /* Address of the module.  */
+  /* Offset in the DST of the module.  */
   unsigned char modbeg[4];
 
-  /* Size of the module.  */
+  /* Size of the DST chunk for this module.  */
   unsigned char size[4];
 
   /* Number of psect for this module.  */
@@ -39,7 +39,10 @@ struct vms_dmt_header
 
 struct vms_dmt_psect
 {
+  /* Address of the psect.  */
   unsigned char start[4];
+
+  /* Length of the psect.  */
   unsigned char length[4];
 };
 #endif /* _VMS_DMT_H */