diff --git a/test/trefer.c b/test/trefer.c
index 651557f163..bb27695f29 100644
--- a/test/trefer.c
+++ b/test/trefer.c
@@ -316,7 +316,7 @@ test_reference_region(void)
     MESSAGE(5, ("Testing Dataset Region Reference Functions\n"));
 
     /* Allocate write & read buffers */
-    wbuf=malloc(sizeof(hdset_reg_ref_t)*SPACE1_DIM1);
+    wbuf=calloc(sizeof(hdset_reg_ref_t)*SPACE1_DIM1);
     rbuf=malloc(sizeof(hdset_reg_ref_t)*SPACE1_DIM1);
     dwbuf=malloc(sizeof(uint8_t)*SPACE2_DIM1*SPACE2_DIM2);
     drbuf=calloc(sizeof(uint8_t),SPACE2_DIM1*SPACE2_DIM2);
diff --git a/tools/h5ls.c b/tools/h5ls.c
index 1dfe647dc4..acd8c9e87b 100644
--- a/tools/h5ls.c
+++ b/tools/h5ls.c
@@ -1000,6 +1000,13 @@ dump_dataset_values(hid_t dset)
     info.line_ncols = width_g;
     info.line_multi_new = 1;
     if (label_g) info.cmpd_name = "%s=";
+    
+    /*
+     * If a compound datatype is split across multiple lines then indent
+     * the continuation line.
+     */
+    info.line_pre  = "        %s ";
+    info.line_cont = "        %s  ";
 
     if (hexdump_g) {
 	/*
@@ -1018,14 +1025,6 @@ dump_dataset_values(hid_t dset)
 	info.line_pre ="        %s \"";
 	info.line_suf = "\"";
     }
-
-
-    /*
-     * If a compound datatype is split across multiple lines then add an
-     * ellipsis to the beginning of the continuation line.
-     */
-    info.line_pre  = "        %s ";
-    info.line_cont = "        %s  ";
     
     /*
      * Print all the values.
diff --git a/tools/h5tools.c b/tools/h5tools.c
index 40cc9f59d2..226b0364ea 100644
--- a/tools/h5tools.c
+++ b/tools/h5tools.c
@@ -186,6 +186,7 @@ h5dump_str_append(h5dump_str_t *str/*in,out*/, const char *fmt, ...)
 	    str->len += nchars;
 	    break;
 	}
+	
 	/* Try again with twice as much space */
 	str->nalloc *= 2;
 	str->s = realloc(str->s, str->nalloc);
@@ -444,6 +445,112 @@ h5dump_escape(char *s/*in,out*/, size_t size, int escape_spaces)
     return s;
 }
 
+
+/*-------------------------------------------------------------------------
+ * Function:	h5dump_is_zero
+ *
+ * Purpose:	Determines if memory is initialized to all zero bytes.
+ *
+ * Return:	TRUE if all bytes are zero; FALSE otherwise
+ *
+ * Programmer:	Robb Matzke
+ *              Monday, June  7, 1999
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+static hbool_t
+h5dump_is_zero(const void *_mem, size_t size)
+{
+    const unsigned char *mem = (const unsigned char*)_mem;
+    while (size-- > 0) {
+	if (mem[size]) return FALSE;
+    }
+    return TRUE;
+}
+
+
+/*-------------------------------------------------------------------------
+ * Function:	h5dump_region
+ *
+ * Purpose:	Prints information about a dataspace region by appending
+ *		the information to the specified string.
+ *
+ * Return:	Success:	0
+ *
+ *		Failure:	NULL
+ *
+ * Programmer:	Robb Matzke
+ *              Monday, June  7, 1999
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+h5dump_region(hid_t region, h5dump_str_t *str/*in,out*/)
+{
+    hssize_t	nblocks, npoints, i;
+    hsize_t	*ptdata;
+    int		j;
+    int		ndims = H5Sget_simple_extent_ndims(region);
+
+    /*
+     * These two functions fail if the region does not have blocks or points,
+     * respectively. They do not currently know how to translate from one to
+     * the other.
+     */
+    H5E_BEGIN_TRY {
+	nblocks = H5Sget_select_hyper_nblocks(region);
+	npoints = H5Sget_select_elem_npoints(region);
+    } H5E_END_TRY;
+    h5dump_str_append(str, "{");
+
+    /* Print block information */
+    if (nblocks>0) {
+	ptdata = malloc(nblocks*ndims*2*sizeof(ptdata[0]));
+	H5Sget_select_hyper_blocklist(region, 0, nblocks, ptdata);
+	for (i=0; i<nblocks; i++) {
+	    h5dump_str_append(str, "%sBlk%lu: ",
+			      i?","OPTIONAL_LINE_BREAK" ":"",
+			      (unsigned long)i);
+
+	    /* Start coordinates and opposite corner */
+	    for (j=0; j<ndims; j++) {
+		h5dump_str_append(str, "%s%lu", j?",":"(",
+				  (unsigned long)(ptdata[i*2*ndims+j]));
+	    }
+	    for (j=0; j<ndims; j++) {
+		h5dump_str_append(str, "%s%lu", j?",":")-(",
+				  (unsigned long)(ptdata[i*2*ndims+j+ndims]));
+	    }
+	    h5dump_str_append(str, ")");
+	}
+	free(ptdata);
+    }
+
+    /* Print point information */
+    if (npoints>0) {
+	ptdata = malloc(npoints*ndims*sizeof(ptdata[0]));
+	H5Sget_select_elem_pointlist(region, 0, npoints, ptdata);
+	for (i=0; i<npoints; i++) {
+	    h5dump_str_append(str, "%sPt%lu: ",
+			      i?","OPTIONAL_LINE_BREAK" ":"",
+			      (unsigned long)i);
+	    for (j=0; j<ndims; j++) {
+		h5dump_str_append(str, "%s%lu", j?",":"(",
+				  (unsigned long)(ptdata[i*ndims+j]));
+	    }
+	    h5dump_str_append(str, ")");
+	}
+	free(ptdata);
+    }
+    
+    h5dump_str_append(str, "}");
+    return 0;
+}
+
 
 /*-------------------------------------------------------------------------
  * Function:	h5dump_sprint
@@ -477,10 +584,11 @@ h5dump_sprint(h5dump_str_t *str/*in,out*/, const h5dump_t *info,
 {
     size_t	i, n, offset, size, dims[H5S_MAX_RANK], nelmts, start;
     char	*name, quote='\0';
-    hid_t	memb;
-    int		nmembs, j, k, ndims;
+    hid_t	memb, obj, region;
+    int		nmembs, j, k, ndims, otype;
     static char	fmt_llong[8], fmt_ullong[8];
     H5T_str_t 	pad;
+    H5G_stat_t	sb;
     int		repeat_threshold; /*-1 means any amount of repeat allowed*/
 
     if ((programtype == UNKNOWN) || (programtype == H5LS)) {
@@ -746,35 +854,61 @@ h5dump_sprint(h5dump_str_t *str/*in,out*/, const h5dump_t *info,
     } else if (H5Tequal(type, H5T_STD_REF_DSETREG)) {
 	/*
 	 * Dataset region reference -- show the type and OID of the referenced
-	 *object, but we are unable to show the region yet because there isn't
-	 *enough support in the data space layer.  - rpm 19990604
+	 * object, but we are unable to show the region yet because there
+	 * isn't enough support in the data space layer.  - rpm 19990604
 	 */
-	int otype = H5Rget_object_type(container, vp);
-	hid_t obj = H5Rdereference(container, H5R_DATASET_REGION, vp);
-	switch (otype) {
-	case H5G_GROUP:
-	    h5dump_str_append(str, "GRP-");
-	    H5Gclose(obj);
-	    break;
-	case H5G_DATASET:
-	    h5dump_str_append(str, "DSET-");
+	if (h5dump_is_zero(vp, H5Tget_size(type))) {
+	    h5dump_str_append(str, "NULL");
+	} else {
+	    obj = H5Rdereference(container, H5R_DATASET_REGION, vp);
+	    region = H5Rget_region(container, H5R_DATASET_REGION, vp);
+	    H5Gget_objinfo(obj, ".", FALSE, &sb);
+	    h5dump_str_append(str, "DSET-%lu:%lu:%lu:%lu-",
+			      sb.fileno[1], sb.fileno[0],
+			      sb.objno[1], sb.objno[0]);
+	    h5dump_region(region, str);
+	    H5Sclose(region);
 	    H5Dclose(obj);
-	    break;
-	case H5G_TYPE:
-	    h5dump_str_append(str, "TYPE-");
-	    H5Tclose(obj);
-	    break;
-	default:
-	    h5dump_str_append(str, "%u-", otype);
-	    /* unable to close `obj' since we don't know the type */
-	    break;
 	}
-	    
+	
+    } else if (H5Tequal(type, H5T_STD_REF_OBJ)) {
+	/*
+	 * Object references -- show the type and OID of the referenced
+	 * object.
+	 */
+	if (h5dump_is_zero(vp, H5Tget_size(type))) {
+	    h5dump_str_append(str, "NULL");
+	} else {
+	    otype = H5Rget_object_type(container, vp);
+	    obj = H5Rdereference(container, H5R_OBJECT, vp);
+	    H5Gget_objinfo(obj, ".", FALSE, &sb);
 
-	/* OID */
+	    /* Print object type and close object */
+	    switch (otype) {
+	    case H5G_GROUP:
+		h5dump_str_append(str, "GRP");
+		H5Gclose(obj);
+		break;
+	    case H5G_DATASET:
+		h5dump_str_append(str, "DSET");
+		H5Dclose(obj);
+		break;
+	    case H5G_TYPE:
+		h5dump_str_append(str, "TYPE");
+		H5Tclose(obj);
+		break;
+	    default:
+		h5dump_str_append(str, "%u-", otype);
+		/* unable to close `obj' since we don't know the type */
+		break;
+	    }
 
-	/* SPACE */
-	    
+	    /* Print OID */
+	    h5dump_str_append(str, "-%lu:%lu:%lu:%lu",
+			      sb.fileno[1], sb.fileno[0],
+			      sb.objno[1], sb.objno[0]);
+	}
+	
     } else {
 	h5dump_str_append(str, "0x");
 	n = H5Tget_size(type);