diff -ru psycopg2-2.0.12.old/setup.py psycopg2-2.0.12/setup.py
--- psycopg2-2.2.1.old/setup.py	2009-08-09 17:10:43.000000000 +0200
+++ psycopg2-2.2.1/setup.py	2009-08-11 08:28:59.606981267 +0200
@@ -144,7 +144,9 @@
         elif compiler_is_mingw:
             # Default MinGW compilation of Python extensions on Windows uses
             # only -O:
-            extra_compiler_args.append('-O3')
+            extra_compiler_args.append('-O2')
+            extra_compiler_args.append('-march=i486')
+            extra_compiler_args.append('-mtune=i686')
 
             # GCC-compiled Python on non-Windows platforms is built with strict
             # aliasing disabled, but that must be done explicitly on Windows to