diff --git a/harbour/ChangeLog b/harbour/ChangeLog
index ce013461b6..bd98d04755 100644
--- a/harbour/ChangeLog
+++ b/harbour/ChangeLog
@@ -1,3 +1,9 @@
+19990831-22:49 EDT Paul Tucker <ptucker@sympatico.ca>
+  * include/set.h
+    source/rtl/set.c
+    Set(_SET_DEBUG) now returns Logical as in Clipper 5.2 and 5.3 operation.
+    (Clipper 5.3 docs are incorrect)
+
 19990831-23:10 GMT+1 Victor Szel <info@szelvesz.hu>
   * source/rtl/itemapi.c
     include/itemapi.h
diff --git a/harbour/include/set.h b/harbour/include/set.h
index 4564d92b67..28265d7ac0 100644
--- a/harbour/include/set.h
+++ b/harbour/include/set.h
@@ -32,6 +32,8 @@
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA (or visit
    their web site at http://www.gnu.org/).
 
+   V 1.25   Paul Tucker                 Converted HB_SET_DEBUG back to Logical.
+                                        Clipper 5.3 docs are incorrect on this.
    V 1.19   Victor Szel                 #include <x> changed to #include "x".
    V 1.18   David G. Holm               Added INKEY_EXTENDED to allow some
                                         platforms to select between normal
@@ -162,7 +164,7 @@ typedef struct
    BOOL   HB_SET_UNIQUE;
    BOOL   HB_SET_DELETED;
    BOOL   HB_SET_CANCEL;
-   int    HB_SET_DEBUG;
+   BOOL   HB_SET_DEBUG;
    int    HB_SET_TYPEAHEAD;
    char   HB_SET_COLOR[ 64 ];
    HB_cursor_enum HB_SET_CURSOR;
diff --git a/harbour/source/rtl/set.c b/harbour/source/rtl/set.c
index a8edbc0039..e0b92af99a 100644
--- a/harbour/source/rtl/set.c
+++ b/harbour/source/rtl/set.c
@@ -29,6 +29,8 @@
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA (or visit
    their web site at http://www.gnu.org/).
 
+   V 1.62   Paul Tucker                 Converted HB_SET_DEBUG back to Logical.
+                                        Clipper 5.3 docs are incorrect on this.
    V 1.51   Victor Szel                 #include <x> changed to #include "x".
    V 1.49   Paul Tucker                 Changed parameter passing checks
                                         in call to hb_setColor() to account
@@ -474,10 +476,10 @@ HARBOUR HB___SETCENTURY( void )
  *                   SET CENTURY modifies the date format. SET CENTURY ON
  *                   replaces the "y"s with "YYYY". SET CENTURY OFF replaces
  *                   the "y"s with "YY".
- *              _SET_DEBUG       <nStatus>
- *                   When set to 1, pressing Alt+D activates the debugger.
- *                   When set to 0, which is the default, Alt+D can be read
- *                   by INKEY().
+ *              _SET_DEBUG       <lStatus>
+ *                   When set to .t., pressing Alt+D activates the debugger.
+ *                   When set to .f., which is the default, Alt+D can be read
+ *                   by INKEY(). (Also affected by AltD(1) and AltD(0))
  *              _SET_DECIMALS    <nNumberOfDecimals>
  *                   Sets the number of decimal digits to use when displaying
  *                   printing numeric values when SET FIXED is ON. Defaults to
@@ -706,8 +708,8 @@ HARBOUR HB_SET( void )
          if( args > 1 ) hb_set.HB_SET_DATEFORMAT = set_string( pArg2, hb_set.HB_SET_DATEFORMAT );
          break;
       case HB_SET_DEBUG      :
-         hb_retni( hb_set.HB_SET_DEBUG );
-         if( args > 1 ) hb_set.HB_SET_DEBUG = set_number( pArg2, hb_set.HB_SET_DEBUG );
+         hb_retl( hb_set.HB_SET_DEBUG );
+         if( args > 1 ) hb_set.HB_SET_DEBUG = set_logical( pArg2 );
          break;
       case HB_SET_DECIMALS   :
          hb_retni( hb_set.HB_SET_DECIMALS );
@@ -911,7 +913,7 @@ void hb_setInitialize( void )
    hb_set.HB_SET_CURSOR = SC_NORMAL;
    hb_set.HB_SET_DATEFORMAT = ( char * ) hb_xgrab( 9 );
    memcpy( hb_set.HB_SET_DATEFORMAT, "mm/dd/yy", 9 );
-   hb_set.HB_SET_DEBUG = 0;
+   hb_set.HB_SET_DEBUG = FALSE;
    hb_set.HB_SET_DECIMALS = 2;
    hb_set.HB_SET_DEFAULT = ( char * ) hb_xgrab( 1 );
    hb_set.HB_SET_DEFAULT[ 0 ] = '\0';