diff --git a/configure.in b/configure.in
index fffeabad4a..ce7c504a3a 100644
--- a/configure.in
+++ b/configure.in
@@ -131,6 +131,7 @@ AC_CANONICAL_HOST
 MATH_LIB=-lm
 AC_MSG_CHECKING([for native Win32])
 LIB_EXE_MACHINE_FLAG=X86
+EXE_MANIFEST_ARCHITECTURE=X86
 case "$host" in
   *-*-mingw*)
     os_win32=yes
@@ -139,6 +140,7 @@ case "$host" in
     case "$host" in
     x86_64-*-*)
       LIB_EXE_MACHINE_FLAG=X64
+      EXE_MANIFEST_ARCHITECTURE=AMD64
       ;;
     esac
     ;;
@@ -149,6 +151,7 @@ esac
 AC_MSG_RESULT([$os_win32])
 
 AC_SUBST(LIB_EXE_MACHINE_FLAG)
+AC_SUBST(EXE_MANIFEST_ARCHITECTURE)
 
 case $host in
   *-*-linux*)
diff --git a/gtk/Makefile.am b/gtk/Makefile.am
index c3d950f47a..291cbf2863 100644
--- a/gtk/Makefile.am
+++ b/gtk/Makefile.am
@@ -1027,7 +1027,7 @@ gtk-update-icon-cache.exe.manifest:
 	(echo '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>' ; \
 	 echo '<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">' ; \
 	 echo '  <assemblyIdentity version="1.0.0.0"' ; \
-	 echo '     processorArchitecture="'$(LIB_EXE_MACHINE_FLAG)'"' ; \
+	 echo '     processorArchitecture="'$(EXE_MANIFEST_ARCHITECTURE)'"' ; \
 	 echo '     name="gtk-update-icon-cache.exe"' ; \
 	 echo '     type="win32"/>' ; \
 	 echo '  <!-- Identify the application security requirements. -->' ; \