diff --git a/ChangeLog b/ChangeLog
index c2caa5d9..cf161dd9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -158,6 +158,7 @@ xx/xx/2005 - 2.0.0-WIP
 	  FileNameDirty to indicate that FILE_NAME attributes need update.
 	  At least after attribute resize we leave absolutely consist
 	  volume.  (Yura)
+	- Update attribute definition handling.  (Anton, Yura)
 
 04/09/2004 - 1.9.4 - Urgent bug fixes.
 
diff --git a/include/ntfs/layout.h b/include/ntfs/layout.h
index f8d9f0f9..f8652e06 100644
--- a/include/ntfs/layout.h
+++ b/include/ntfs/layout.h
@@ -539,19 +539,37 @@ typedef enum {
 
 /*
  * The flags (32-bit) describing attribute properties in the attribute
- * definition structure. FIXME: This information is from Regis's information
- * and, according to him, it is not certain and probably incomplete.
- * The INDEXABLE flag is fairly certainly correct as only the file name
- * attribute has this flag set and this is the only attribute indexed in NT4.
+ * definition structure.  FIXME: This information is based on Regis's
+ * information and, according to him, it is not certain and probably
+ * incomplete.  The INDEXABLE flag is fairly certainly correct as only the file
+ * name attribute has this flag set and this is the only attribute indexed in
+ * NT4.
  */
 typedef enum {
-	INDEXABLE	    = const_cpu_to_le32(0x02),	/* Attribute can be
-							   indexed. */
-	NEED_TO_REGENERATE  = const_cpu_to_le32(0x40),	/* Need to regenerate
-							   during regeneration
-							   phase. */
-	CAN_BE_NON_RESIDENT = const_cpu_to_le32(0x80),	/* Attribute can be
-							   non-resident. */
+	ATTR_DEF_INDEXABLE	= const_cpu_to_le32(0x02), /* Attribute can be
+					indexed. */
+	ATTR_DEF_MULTIPLE	= const_cpu_to_le32(0x04), /* Attribute type
+					can be present multiple times in the
+					mft records of an inode. */
+	ATTR_DEF_NOT_ZERO	= const_cpu_to_le32(0x08), /* Attribute value
+					must contain at least one non-zero
+					byte. */
+	ATTR_DEF_INDEXED_UNIQUE	= const_cpu_to_le32(0x10), /* Attribute must be
+					indexed and the attribute value must be
+					unique for the attribute type in all of
+					the mft records of an inode. */
+	ATTR_DEF_NAMED_UNIQUE	= const_cpu_to_le32(0x20), /* Attribute must be
+					named and the name must be unique for
+					the attribute type in all of the mft
+					records of an inode. */
+	ATTR_DEF_RESIDENT	= const_cpu_to_le32(0x40), /* Attribute must be
+					resident. */
+	ATTR_DEF_ALWAYS_LOG	= const_cpu_to_le32(0x80), /* Always log
+					modifications to this attribute,
+					regardless of whether it is resident or
+					non-resident.  Without this, only log
+					modifications if the attribute is
+					resident. */
 } ATTR_DEF_FLAGS;
 
 /*
diff --git a/libntfs/attrib.c b/libntfs/attrib.c
index cf963d6e..c22a15de 100644
--- a/libntfs/attrib.c
+++ b/libntfs/attrib.c
@@ -2358,21 +2358,16 @@ int ntfs_attr_can_be_non_resident(const ntfs_volume *vol, const ATTR_TYPES type)
 {
 	ATTR_DEF *ad;
 
-	/*
-	 * $DATA is always allowed to be non-resident even if $AttrDef does not
-	 * specify this in the flags of the $DATA attribute definition record.
-	 */
-	if (type == AT_DATA)
-		return 0;
 	/* Find the attribute definition record in $AttrDef. */
 	ad = ntfs_attr_find_in_attrdef(vol, type);
 	if (!ad)
 		return -1;
 	/* Check the flags and return the result. */
-	if (ad->flags & CAN_BE_NON_RESIDENT)
-		return 0;
-	errno = EPERM;
-	return -1;
+	if (ad->flags & ATTR_DEF_RESIDENT) {
+		errno = EPERM;
+		return -1;
+	}
+	return 0;
 }
 
 /**