diff --git a/harbour/ChangeLog b/harbour/ChangeLog
index b216334d9e..6bd4eb2105 100644
--- a/harbour/ChangeLog
+++ b/harbour/ChangeLog
@@ -16,6 +16,20 @@
    The license applies to all entries newer than 2009-04-28.
 */
 
+2011-10-04 23:59 UTC+0200 Viktor Szakats (harbour.01 syenar.hu)
+  * include/hbthread.h
+  * include/hbsetup.h
+  * src/3rd/zlib/Makefile
+  * utils/hbmk2/hbmk2.prg
+  * config/detplat.mk
+  * config/global.mk
+  + config/aix
+  + config/aix/libs.mk
+  + config/aix/gcc.mk
+  + config/aix/global.mk
+    + added IBM AIX support to Harbour
+      Patch by Aleksander Czajczynski
+
 2011-10-04 23:51 UTC+0200 Viktor Szakats (harbour.01 syenar.hu)
   * tests/testpre.prg
     ! updated for Harbour 3.1.x
diff --git a/harbour/config/aix/gcc.mk b/harbour/config/aix/gcc.mk
new file mode 100644
index 0000000000..8048146d81
--- /dev/null
+++ b/harbour/config/aix/gcc.mk
@@ -0,0 +1,100 @@
+#
+# $Id$
+#
+
+ifeq ($(HB_BUILD_MODE),cpp)
+   HB_CMP := g++
+else
+   HB_CMP := gcc
+endif
+
+OBJ_EXT := .o
+LIB_PREF := lib
+LIB_EXT := .a
+
+HB_DYN_COPT := -DHB_DYNLIB -fPIC
+
+CC := $(HB_CCACHE) $(HB_CCPREFIX)$(HB_CMP)$(HB_CCPOSTFIX)
+CC_IN := -c
+CC_OUT := -o
+
+CFLAGS += -I. -I$(HB_HOST_INC)
+
+# uncomment this if you want to force creating 64bit binaries
+#CFLAGS += -maix64
+#LDFLAGS += -maix64 -Wl,-b64
+#DFLAGS += -maix64 -Wl,-b64
+#ARFLAGS += -X64
+
+ifneq ($(HB_BUILD_WARN),no)
+   CFLAGS += -W -Wall
+else
+   CFLAGS += -Wmissing-braces -Wreturn-type -Wformat
+   ifneq ($(HB_BUILD_MODE),cpp)
+      CFLAGS += -Wimplicit-int -Wimplicit-function-declaration
+   endif
+endif
+
+ifneq ($(HB_BUILD_OPTIM),no)
+   CFLAGS += -O3
+endif
+
+ifeq ($(HB_BUILD_DEBUG),yes)
+   CFLAGS += -g
+endif
+
+LD := $(CC)
+LD_OUT := -o
+
+LIBPATHS := $(foreach dir,$(LIB_DIR) $(SYSLIBPATHS),-L$(dir))
+LDLIBS := $(foreach lib,$(HB_USER_LIBS) $(LIBS) $(SYSLIBS),-l$(lib))
+
+LDFLAGS += $(LIBPATHS) # -Wl,-bnoquiet
+
+# uncomment following block for AIX linker workaround (linking all symbols issue)
+# order of libraries is more important this way
+
+define aix_ld_hblib
+   $(LD) -Wl,-r,-bgc,-bkeepfile:__applnk__.o -nostartfiles $(LDFLAGS) $(HB_LDFLAGS) $(HB_USER_LDFLAGS) -o__apptmp__.o __applnk__.o -l$(lib)
+   mv __apptmp__.o __applnk__.o
+
+endef
+
+define aix_ld
+   $(LD) -Wl,-r $(LDFLAGS) $(HB_LDFLAGS) $(HB_USER_LDFLAGS) -o__apptmp__.o $(^F)
+   mv __apptmp__.o __applnk__.o
+   $(foreach lib,$(HB_USER_LIBS) $(LIBS),$(aix_ld_hblib))
+   $(LD) -nostartfiles $(LDFLAGS) $(HB_LDFLAGS) $(HB_USER_LDFLAGS) $(LD_OUT)$(subst /,$(DIRSEP),$(BIN_DIR)/$@) __applnk__.o $(foreach lib,$(SYSLIBS),-l$(lib)) $(LDSTRIP)
+   $(RM) __applnk__.o
+endef
+
+LD_RULE = $(aix_ld)
+
+# end of workaround block
+
+AR := $(HB_CCPREFIX)ar
+AR_RULE = ( $(AR) $(ARFLAGS) $(HB_AFLAGS) $(HB_USER_AFLAGS) rc $(LIB_DIR)/$@ $(^F) $(ARSTRIP) ) || ( $(RM) $(LIB_DIR)/$@ && $(FALSE) )
+
+DY := $(CC)
+DFLAGS += -shared -Wl,-G $(LIBPATHS)
+# TOFIX: CHECKME, there was space between -o and output name
+#DY_OUT := -o$(subst x,x, )
+DY_OUT := $(LD_OUT)
+DLIBS := $(foreach lib,$(HB_USER_LIBS) $(SYSLIBS),-l$(lib))
+
+# NOTE: The empty line directly before 'endef' HAVE TO exist!
+#define dynlib_object
+#   @$(ECHO) $(ECHOQUOTE)INPUT($(subst \,/,$(file)))$(ECHOQUOTE) >> __dyn__.tmp
+
+#endef
+#define create_dynlib
+#   $(if $(wildcard __dyn__.tmp),@$(RM) __dyn__.tmp,)
+#   $(foreach file,$^,$(dynlib_object))
+#   $(DY) $(DFLAGS) $(HB_USER_DFLAGS) $(DY_OUT)$(DYN_DIR)/$@ __dyn__.tmp $(DLIBS) $(DYSTRIP) && $(LN) $(@F) $(DYN_FILE_NVR) && $(LN) $(@F) $(DYN_FILE_CPT)
+#endef
+
+#DY_RULE = $(create_dynlib)
+
+DY_RULE = $(DY) $(DFLAGS) $(HB_USER_DFLAGS) $(DY_OUT)$(DYN_DIR)/$@ $^ $(DLIBS) $(DYSTRIP) && $(LN) $(@F) $(DYN_FILE_NVR) && $(LN) $(@F) $(DYN_FILE_CPT)
+
+include $(TOP)$(ROOT)config/rules.mk
diff --git a/harbour/config/aix/global.mk b/harbour/config/aix/global.mk
new file mode 100644
index 0000000000..c39ee05a1b
--- /dev/null
+++ b/harbour/config/aix/global.mk
@@ -0,0 +1,16 @@
+#
+# $Id$
+#
+
+all : first
+
+BIN_EXT :=
+DYN_EXT := .so
+DYN_PREF := lib
+
+HB_GT_LIBS += gttrm
+
+ifneq ($(filter $(HB_BUILD_STRIP),all bin),)
+   LDSTRIP := -s
+   DYSTRIP := -s
+endif
diff --git a/harbour/config/aix/libs.mk b/harbour/config/aix/libs.mk
new file mode 100644
index 0000000000..713af76e7e
--- /dev/null
+++ b/harbour/config/aix/libs.mk
@@ -0,0 +1,44 @@
+#
+# $Id$
+#
+
+# When compiling and linking with -pthread, the library search path should 
+# include -L/usr/lib/threads at the beginning of the path.
+# http://www.ibm.com/developerworks/aix/library/au-gnu.html
+# (libc is there)
+ifeq ($(HB_LINKING_VMMT),yes)
+   SYSLIBPATHS := /usr/lib/threads
+else
+   SYSLIBPATHS :=
+endif
+
+ifneq ($(HB_LINKING_RTL),)
+   ifeq ($(HB_LIBNAME_CURSES),)
+      HB_LIBNAME_CURSES := xcurses
+   endif
+   ifneq ($(HB_HAS_CURSES),)
+      SYSLIBS += $(HB_LIBNAME_CURSES)
+   endif
+   ifneq ($(HB_HAS_SLANG),)
+      SYSLIBS += slang
+   endif
+   ifneq ($(HB_HAS_X11),)
+      SYSLIBS += X11
+      SYSLIBPATHS += /usr/X11R6/lib
+   endif
+   ifneq ($(HB_HAS_PCRE),)
+      ifeq ($(HB_HAS_PCRE_LOCAL),)
+         SYSLIBS += pcre
+      endif
+   endif
+   ifeq ($(HB_HAS_ZLIB_LOCAL),)
+      SYSLIBS += z
+   endif
+   SYSLIBS += rt
+
+   ifneq ($(HB_LINKING_VMMT),)
+      SYSLIBS += pthread
+   endif
+endif
+
+SYSLIBS += m
diff --git a/harbour/config/detplat.mk b/harbour/config/detplat.mk
index 7dcc083f4f..90c4bebc7e 100644
--- a/harbour/config/detplat.mk
+++ b/harbour/config/detplat.mk
@@ -72,6 +72,10 @@ ifneq ($(findstring QNX,$(_DETPLAT_STR)),)
 else
 ifneq ($(findstring Minix,$(_DETPLAT_STR)),)
    HB_HOST_PLAT := minix
+else
+ifneq ($(findstring AIX,$(_DETPLAT_STR)),)
+   HB_HOST_PLAT := aix
+endif
 endif
 endif
 endif
diff --git a/harbour/config/global.mk b/harbour/config/global.mk
index f7df0e6526..85aff168a0 100644
--- a/harbour/config/global.mk
+++ b/harbour/config/global.mk
@@ -823,7 +823,7 @@ ifeq ($(HB_COMPILER),)
          endif
       endif
    else
-   ifneq ($(filter $(HB_PLATFORM),hpux bsd beos qnx cygwin),)
+   ifneq ($(filter $(HB_PLATFORM),aix hpux bsd beos qnx cygwin),)
       HB_COMP_PATH := $(call find_in_path,gcc)
       ifneq ($(HB_COMP_PATH),)
          HB_COMPILER := gcc
@@ -1494,6 +1494,10 @@ ifneq ($(HB_HOST_PLAT)$(HB_HOST_CPU),$(HB_PLATFORM)$(HB_CPU))
       else
       ifeq ($(HB_PLATFORM),minix)
          HB_PRGFLAGS += -D__PLATFORM__MINIX -D__PLATFORM__UNIX
+      else
+      ifeq ($(HB_PLATFORM),aix)
+         HB_PRGFLAGS += -D__PLATFORM__AIX -D__PLATFORM__UNIX
+      endif
       endif
       endif
       endif
diff --git a/harbour/include/hbsetup.h b/harbour/include/hbsetup.h
index 60b40acdeb..f443747f5b 100644
--- a/harbour/include/hbsetup.h
+++ b/harbour/include/hbsetup.h
@@ -428,6 +428,12 @@
    #endif
 #endif
 
+#ifndef HB_OS_AIX
+   #if defined( _AIX ) || defined( __aix__ )
+      #define HB_OS_AIX
+   #endif
+#endif
+
 #ifndef HB_OS_UNIX
    #if defined( HB_OS_LINUX ) || \
        defined( HB_OS_DARWIN ) || \
@@ -440,7 +446,8 @@
        defined( HB_OS_SYMBIAN ) || \
        defined( HB_OS_ANDROID ) || \
        defined( HB_OS_CYGWIN ) || \
-       defined( HB_OS_MINIX )
+       defined( HB_OS_MINIX ) || \
+       defined( HB_OS_AIX )
       #define HB_OS_UNIX
    #endif
 #endif
diff --git a/harbour/include/hbthread.h b/harbour/include/hbthread.h
index ac9f4bf245..8bbc8ffb8c 100644
--- a/harbour/include/hbthread.h
+++ b/harbour/include/hbthread.h
@@ -65,7 +65,8 @@
       defined( HB_OS_SUNOS ) || defined( HB_OS_HPUX ) || \
       defined( HB_OS_BSD ) || defined( HB_OS_BEOS ) || \
       defined( HB_OS_QNX ) || defined( HB_OS_VXWORKS ) || \
-      defined( HB_OS_SYMBIAN ) || defined( HB_OS_CYGWIN )
+      defined( HB_OS_SYMBIAN ) || defined( HB_OS_CYGWIN ) || \
+      defined( HB_OS_AIX )
 #  include <pthread.h>
 #  define HB_PTHREAD_API
 #  if defined( HB_OS_VXWORKS )
diff --git a/harbour/src/3rd/zlib/Makefile b/harbour/src/3rd/zlib/Makefile
index b6d65b9d5d..eb5c5341ff 100644
--- a/harbour/src/3rd/zlib/Makefile
+++ b/harbour/src/3rd/zlib/Makefile
@@ -37,6 +37,10 @@ ifneq ($(HB_HAS_ZLIB_LOCAL),)
    # To suppress new warnings in version 1.2.5
    ifneq ($(filter $(HB_COMPILER),mingw mingw64 mingwarm cygwin djgpp),)
       HB_CFLAGS += -DNO_VIZ
+   else
+      ifneq ($(filter $(HB_PLATFORM),aix),)
+         HB_CFLAGS += -DNO_VIZ
+      endif
    endif
    include $(TOP)$(ROOT)config/lib.mk
 else
diff --git a/harbour/utils/hbmk2/hbmk2.prg b/harbour/utils/hbmk2/hbmk2.prg
index 03cce0e55f..50fe6bd06f 100644
--- a/harbour/utils/hbmk2/hbmk2.prg
+++ b/harbour/utils/hbmk2/hbmk2.prg
@@ -1329,7 +1329,7 @@ FUNCTION hbmk2( aArgs, nArgTarget, /* @ */ lPause, nLevel )
    cBin_CompPRG := "harbour" + l_cHBPOSTFIX
 
    DO CASE
-   CASE HBMK_ISPLAT( "darwin|bsd|hpux|sunos|beos|qnx|android|vxworks|symbian|linux|cygwin|minix" )
+   CASE HBMK_ISPLAT( "darwin|bsd|hpux|sunos|beos|qnx|android|vxworks|symbian|linux|cygwin|minix|aix" )
       DO CASE
       CASE hbmk[ _HBMK_cPLAT ] == "linux"
          aCOMPSUP := { "gcc", "clang", "icc", "watcom", "sunpro", "open64", "pcc" }
@@ -1639,7 +1639,7 @@ FUNCTION hbmk2( aArgs, nArgTarget, /* @ */ lPause, nLevel )
       IF Empty( hbmk[ _HBMK_cCOMP ] ) .OR. hbmk[ _HBMK_cCOMP ] == "bld"
          IF Len( aCOMPSUP ) == 1
             hbmk[ _HBMK_cCOMP ] := aCOMPSUP[ 1 ]
-         ELSEIF HBMK_ISPLAT( "darwin|bsd|hpux|sunos|beos|qnx|android|vxworks|linux|cygwin|minix" ) .OR. ;
+         ELSEIF HBMK_ISPLAT( "darwin|bsd|hpux|sunos|beos|qnx|android|vxworks|linux|cygwin|minix|aix" ) .OR. ;
                 hbmk[ _HBMK_cCOMP ] == "bld"
             hbmk[ _HBMK_cCOMP ] := hb_Version( HB_VERSION_BUILD_COMP )
             IF AScan( aCOMPSUP, { |tmp | tmp == hbmk[ _HBMK_cCOMP ] } ) == 0
@@ -1943,7 +1943,7 @@ FUNCTION hbmk2( aArgs, nArgTarget, /* @ */ lPause, nLevel )
 
    /* Build with shared libs by default, if we're installed to default system locations. */
 
-   IF lSysLoc .AND. HBMK_ISPLAT( "darwin|bsd|hpux|sunos|beos|qnx|android|vxworks|linux|cygwin" )
+   IF lSysLoc .AND. HBMK_ISPLAT( "darwin|bsd|hpux|sunos|beos|qnx|android|vxworks|linux|cygwin|aix" )
       hbmk[ _HBMK_lSHARED ] := .T.
       hbmk[ _HBMK_lSTATICFULL ] := .F.
    ELSE
@@ -3234,7 +3234,7 @@ FUNCTION hbmk2( aArgs, nArgTarget, /* @ */ lPause, nLevel )
       ENDIF
 
       DO CASE
-      CASE HBMK_ISPLAT( "darwin|bsd|linux|hpux|beos|qnx|android|vxworks|sunos|minix" )
+      CASE HBMK_ISPLAT( "darwin|bsd|linux|hpux|beos|qnx|android|vxworks|sunos|minix|aix" )
          IF Empty( l_cDynLibDir )
             l_aLIBSHARED := { cHarbourDyn + cPostfix }
          ELSE
@@ -3339,7 +3339,8 @@ FUNCTION hbmk2( aArgs, nArgTarget, /* @ */ lPause, nLevel )
            ( hbmk[ _HBMK_cPLAT ] == "darwin"  .AND. hbmk[ _HBMK_cCOMP ] == "pcc" ) .OR. ;
            ( hbmk[ _HBMK_cPLAT ] == "linux"   .AND. hbmk[ _HBMK_cCOMP ] == "pcc" ) .OR. ;
            ( hbmk[ _HBMK_cPLAT ] == "sunos"   .AND. hbmk[ _HBMK_cCOMP ] == "pcc" ) .OR. ;
-           ( hbmk[ _HBMK_cPLAT ] == "minix"   .AND. hbmk[ _HBMK_cCOMP ] == "gcc" )
+           ( hbmk[ _HBMK_cPLAT ] == "minix"   .AND. hbmk[ _HBMK_cCOMP ] == "gcc" ) .OR. ;
+           ( hbmk[ _HBMK_cPLAT ] == "aix"     .AND. hbmk[ _HBMK_cCOMP ] == "gcc" )
 
          #if defined( __PLATFORM__UNIX )
             hbmk[ _HBMK_nCmd_Esc ] := _ESC_NIX
@@ -3556,7 +3557,7 @@ FUNCTION hbmk2( aArgs, nArgTarget, /* @ */ lPause, nLevel )
          ENDIF
 
          IF hbmk[ _HBMK_lPIC ] .AND. ! HBMK_ISPLAT( "darwin|cygwin" )
-            IF HBMK_ISPLAT( "bsd|hpux|sunos|linux|android" )
+            IF HBMK_ISPLAT( "bsd|hpux|sunos|linux|android|aix" )
                AAdd( hbmk[ _HBMK_aOPTC ], "-fPIC" )
             ELSE
                AAdd( hbmk[ _HBMK_aOPTC ], "-fpic" )
@@ -10167,6 +10168,9 @@ STATIC PROCEDURE PlatformPRGFlags( hbmk, aOPTPRG )
       #elif defined( __PLATFORM__CYGWIN )
          AAdd( aUn, "__PLATFORM__CYGWIN" )
          AAdd( aUn, "__PLATFORM__UNIX" )
+      #elif defined( __PLATFORM__AIX )
+         AAdd( aUn, "__PLATFORM__AIX" )
+         AAdd( aUn, "__PLATFORM__UNIX" )
       #endif
 
       #if   defined( __ARCH16BIT__ )
@@ -10241,6 +10245,9 @@ STATIC PROCEDURE PlatformPRGFlags( hbmk, aOPTPRG )
       CASE hbmk[ _HBMK_cPLAT ] == "minix"
          AAdd( aDf, "__PLATFORM__MINIX" )
          AAdd( aDf, "__PLATFORM__UNIX" )
+      CASE hbmk[ _HBMK_cPLAT ] == "aix"
+         AAdd( aDf, "__PLATFORM__AIX" )
+         AAdd( aDf, "__PLATFORM__UNIX" )
       ENDCASE
 
       /* Setup those CPU flags which we can be sure about.
@@ -11265,7 +11272,7 @@ FUNCTION hbmk_KEYW( hbmk, cKeyword, cValue, cOperator )
    CASE "lngc"     ; RETURN hbmk[ _HBMK_lCPP ] != NIL .AND. ! hbmk[ _HBMK_lCPP ]
    CASE "winuni"   ; RETURN hbmk[ _HBMK_lWINUNI ]
    CASE "winansi"  ; RETURN ! hbmk[ _HBMK_lWINUNI ]
-   CASE "unix"     ; RETURN HBMK_ISPLAT( "bsd|hpux|sunos|beos|qnx|android|vxworks|symbian|linux|darwin|cygwin|minix" )
+   CASE "unix"     ; RETURN HBMK_ISPLAT( "bsd|hpux|sunos|beos|qnx|android|vxworks|symbian|linux|darwin|cygwin|minix|aix" )
    CASE "allwin"   ; RETURN HBMK_ISPLAT( "win|wce" )
    CASE "allgcc"   ; RETURN HBMK_ISCOMP( "gcc|mingw|mingw64|mingwarm|djgpp|gccomf|clang|open64|pcc" )
    CASE "allmingw" ; RETURN HBMK_ISCOMP( "mingw|mingw64|mingwarm" )
@@ -11286,7 +11293,7 @@ FUNCTION hbmk_KEYW( hbmk, cKeyword, cValue, cOperator )
    ENDIF
 
    IF ! HBMK_IS_IN( cKeyword, "|win|wce|dos|os2" + ;
-                              "|bsd|hpux|sunos|beos|qnx|android|vxworks|symbian|linux|darwin|cygwin|minix" + ;
+                              "|bsd|hpux|sunos|beos|qnx|android|vxworks|symbian|linux|darwin|cygwin|minix|aix" + ;
                               "|msvc|msvc64|msvcia64|msvcarm" + ;
                               "|pocc|pocc64|poccarm|xcc" + ;
                               "|mingw|mingw64|mingwarm|bcc|watcom" + ;
@@ -12172,6 +12179,7 @@ STATIC PROCEDURE ShowHelp( hbmk, lLong )
       "  - symbian : gcc",;
       "  - cygwin  : gcc",;
       "  - minix   : gcc, clang, ack",;
+      "  - aix     : gcc",;
       "  - sunos   : gcc, sunpro, pcc" }
 
    LOCAL aOpt_Basic := {;