diff --git a/NEWS b/NEWS
index 89230551..cc1633bc 100644
--- a/NEWS
+++ b/NEWS
@@ -10,6 +10,7 @@ What's new in psycopg 2.4.7
     Alexey Borzenkov (:ticket:`#173`).
   - Manually creating `lobject` with the wrong parameter doesn't segfault
     (:ticket:`#187`).
+  - Fixed debug build on Windows, thanks to James Emerton.
 
 
 What's new in psycopg 2.4.6
diff --git a/setup.py b/setup.py
index 0bb486dc..0abc51eb 100644
--- a/setup.py
+++ b/setup.py
@@ -287,12 +287,15 @@ class psycopg_build_ext(build_ext):
             manifest = '_psycopg.vc9.x86.manifest'
             if platform == 'win-amd64':
                 manifest = '_psycopg.vc9.amd64.manifest'
+            try:
+                ext_path = self.get_ext_fullpath(extension.name)
+            except AttributeError:
+                ext_path = os.path.join(self.build_lib,
+                        'psycopg2', '_psycopg.pyd')
             self.compiler.spawn(
                 ['mt.exe', '-nologo', '-manifest',
                  os.path.join('psycopg', manifest),
-                 '-outputresource:%s;2' % (
-                        os.path.join(self.build_lib,
-                                     'psycopg2', '_psycopg.pyd'))])
+                 '-outputresource:%s;2' % ext_path])
 
     def finalize_win32(self):
         """Finalize build system configuration on win32 platform."""