diff --git a/src/include/types_pub.h b/src/include/types_pub.h
index 6b84b53656..edbc1bf22e 100644
--- a/src/include/types_pub.h
+++ b/src/include/types_pub.h
@@ -49,7 +49,7 @@ typedef unsigned long uintptr_t;
 /* API handles                                                    */
 /******************************************************************/
 
-#if defined(_LP64) || defined(__LP64__) || defined(__arch64__) || defined(_WIN64)
+#if defined(_LP64) || defined(__LP64__) || defined(__arch64__) || defined(_WIN64) 
 typedef unsigned int	FB_API_HANDLE;
 #else
 typedef void*		FB_API_HANDLE;
diff --git a/src/jrd/common.h b/src/jrd/common.h
index 02a725f4e2..93c5ba83d5 100644
--- a/src/jrd/common.h
+++ b/src/jrd/common.h
@@ -286,6 +286,9 @@ static inline int sinixz_sigaction(int sig, const struct sinixz_sigaction *act,
 #define I386
 #define IMPLEMENTATION isc_info_db_impl_darwin_x86 /* 70 */
 #endif
+#ifdef __x86_64__
+#define IMPLEMENTATION isc_info_db_impl_darwin_x86 /* 70 */
+#endif
 #define IEEE
 #define QUADCONST(n) (n##LL)
 #define QUADFORMAT "q"
diff --git a/src/jrd/license.h b/src/jrd/license.h
index 8e397359dd..7c3c61efd2 100644
--- a/src/jrd/license.h
+++ b/src/jrd/license.h
@@ -133,7 +133,7 @@
 #endif
 
 #ifdef DARWIN
-#ifdef i386
+#if defined(i386) || (__x86_64__)
 #define FB_PLATFORM	"UI"	/* Darwin/Intel */
 #endif
 #if defined (DARWIN) && defined (_powerpc_)
diff --git a/src/jrd/pag.cpp b/src/jrd/pag.cpp
index fb9b43626d..318966d08c 100644
--- a/src/jrd/pag.cpp
+++ b/src/jrd/pag.cpp
@@ -315,7 +315,7 @@ const SSHORT CLASS		= CLASS_NETBSD_I386;
 #endif
 
 #ifdef DARWIN
-#ifdef i386
+#if defined(i386) || defined (__x86_64__)
 const SSHORT CLASS		= CLASS_DARWIN_I386;
 #endif
 #ifdef powerpc
diff --git a/src/remote/xdr.cpp b/src/remote/xdr.cpp
index 33446bc817..e63db47528 100644
--- a/src/remote/xdr.cpp
+++ b/src/remote/xdr.cpp
@@ -39,7 +39,7 @@
 // The simpliest way to check it is to issue
 // "select abs(2.0/3.0) from rdb$database" from correct client
 // It will return big strange value in case of invalid define
-#if defined(i386) || defined(I386) || defined(_M_IX86) || defined(AMD64) || defined(MIPSEL)
+#if defined(i386) || defined(I386) || defined(_M_IX86) || defined(AMD64) || defined(MIPSEL) || defined(__x86_64__)
 #define		SWAP_DOUBLE
 #elif defined(sparc) || defined(PowerPC) || defined(PPC) || defined(__ppc__) || defined(HPUX) || defined(MIPS)
 #undef		SWAP_DOUBLE