diff --git a/harbour/ChangeLog b/harbour/ChangeLog
index 5b77824a55..36f9a59aef 100644
--- a/harbour/ChangeLog
+++ b/harbour/ChangeLog
@@ -16,6 +16,15 @@
    The license applies to all entries newer than 2009-04-28.
 */
 
+2011-06-12 13:33 UTC+0200 Przemyslaw Czerpak (druzus/at/priv.onet.pl)
+  * harbour/contrib/hblzf/3rd/liblzf/lzf_c.c
+    ! use __int64 instead of _int64 in WIN64 builds
+      Some MinGW64 versions (i.e. tdm64-gcc-4.5.2.exe_ do not support
+      _int64 as default type.
+
+  * harbour/contrib/hblzf/3rd/liblzf/liblzf.dif
+    * regenerated with: ../../../../bin/hb3rdpat.hbs -rediff
+
 2011-06-12 13:16 UTC+0200 Przemyslaw Czerpak (druzus/at/priv.onet.pl)
   * harbour/src/rtl/strtran.c
     ! rewritten STRTRAN() to fix incompatibilities with Clipper and fatal
diff --git a/harbour/contrib/hblzf/3rd/liblzf/liblzf.dif b/harbour/contrib/hblzf/3rd/liblzf/liblzf.dif
index 9118431406..492ce65e4e 100644
--- a/harbour/contrib/hblzf/3rd/liblzf/liblzf.dif
+++ b/harbour/contrib/hblzf/3rd/liblzf/liblzf.dif
@@ -1,6 +1,18 @@
+diff -urN liblzf.orig/lzf_c.c liblzf/lzf_c.c
+--- liblzf.orig/lzf_c.c	2011-06-12 13:27:46.566657457 +0200
++++ liblzf/lzf_c.c	2011-06-12 13:27:46.566657457 +0200
+@@ -120,7 +120,7 @@
+    * special workaround for it.
+    */
+ #if defined (WIN32) && defined (_M_X64)
+-  unsigned _int64 off; /* workaround for missing POSIX compliance */
++  unsigned __int64 off; /* workaround for missing POSIX compliance */
+ #else
+   unsigned long off;
+ #endif
 diff -urN liblzf.orig/lzf.h liblzf/lzf.h
---- liblzf.orig/lzf.h	2011-03-03 16:32:45.540929609 +0100
-+++ liblzf/lzf.h	2011-03-03 16:32:45.570926090 +0100
+--- liblzf.orig/lzf.h	2011-06-12 13:27:46.564657718 +0200
++++ liblzf/lzf.h	2011-06-12 13:27:46.564657718 +0200
 @@ -37,6 +37,10 @@
  #ifndef LZF_H
  #define LZF_H
@@ -23,8 +35,8 @@ diff -urN liblzf.orig/lzf.h liblzf/lzf.h
  #endif
  
 diff -urN liblzf.orig/lzfP.h liblzf/lzfP.h
---- liblzf.orig/lzfP.h	2011-03-03 16:32:45.590925701 +0100
-+++ liblzf/lzfP.h	2011-03-03 16:32:45.590925701 +0100
+--- liblzf.orig/lzfP.h	2011-06-12 13:27:46.568657801 +0200
++++ liblzf/lzfP.h	2011-06-12 13:27:46.568657801 +0200
 @@ -141,7 +141,7 @@
  #endif
  
diff --git a/harbour/contrib/hblzf/3rd/liblzf/lzf_c.c b/harbour/contrib/hblzf/3rd/liblzf/lzf_c.c
index bc07084b8f..fc4a6d12e8 100644
--- a/harbour/contrib/hblzf/3rd/liblzf/lzf_c.c
+++ b/harbour/contrib/hblzf/3rd/liblzf/lzf_c.c
@@ -120,7 +120,7 @@ lzf_compress (const void *const in_data, unsigned int in_len,
    * special workaround for it.
    */
 #if defined (WIN32) && defined (_M_X64)
-  unsigned _int64 off; /* workaround for missing POSIX compliance */
+  unsigned __int64 off; /* workaround for missing POSIX compliance */
 #else
   unsigned long off;
 #endif