diff --git a/PCbuild/build_ssl.py b/PCbuild/build_ssl.py
index 2ccceec..f24c906 100644
--- a/PCbuild/build_ssl.py
+++ b/PCbuild/build_ssl.py
@@ -102,8 +102,11 @@
     """
     if not os.path.isfile(m32):
         return
-    with open(m32) as fin:
-        with open(makefile, 'w') as fout:
+    # 2.4 compatibility
+    fin = open(m32)
+    if 1: # with open(m32) as fin:
+        fout = open(makefile, 'w')
+        if 1: # with open(makefile, 'w') as fout:
             for line in fin:
                 line = line.replace("=tmp32", "=tmp64")
                 line = line.replace("=out32", "=out64")
@@ -121,9 +124,13 @@
     """
     if not os.path.isfile(makefile):
         return
-    with open(makefile) as fin:
+    # 2.4 compatibility
+    fin = open(makefile)
+    if 1: # with open(makefile) as fin:
         lines = fin.readlines()
-    with open(makefile, 'w') as fout:
+        fin.close()
+    fout = open(makefile, 'w')
+    if 1: # with open(makefile, 'w') as fout:
         for line in lines:
             if line.startswith("PERL="):
                 continue
@@ -139,6 +146,7 @@
                         line = line + noalgo
                 line = line + '\n'
             fout.write(line)
+    fout.close()
 
 def run_configure(configure, do_script):
     print("perl Configure "+configure)
diff --git a/PCbuild/readme.txt b/PCbuild/readme.txt
index f8b3f65..4d2f9b6 100644
--- a/PCbuild/readme.txt
+++ b/PCbuild/readme.txt
@@ -303,7 +303,8 @@
 ------------------
 
 The build process for AMD64 / x64 is very similar to standard builds. You just
-have to set x64 as platform. 
+have to set x64 as platform. In addition, the HOST_PYTHON environment variable
+must point to a Python interpreter (at least 2.4), to support cross-compilation.
 
 Building Python Using the free MS Toolkit Compiler
 --------------------------------------------------
diff --git a/PCbuild/x64.vsprops b/PCbuild/x64.vsprops
index c7eabbe..0720084 100644
--- a/PCbuild/x64.vsprops
+++ b/PCbuild/x64.vsprops
@@ -15,4 +15,8 @@
 		Name="VCLinkerTool"
 		TargetMachine="17"
 	/>
+	<UserMacro
+		Name="PythonExe"
+		Value="$(HOST_PYTHON)"
+	/>
 </VisualStudioPropertySheet>