Index: Lib/distutils/ccompiler.py
===================================================================
--- Lib/distutils/ccompiler.py	(revision 66567)
+++ Lib/distutils/ccompiler.py	(working copy)
@@ -73,6 +73,7 @@
     static_lib_format = None            # format string
     shared_lib_format = None            # prob. same as static_lib_format
     exe_extension = None                # string
+    lib_types = ["static", "shared"]    # list of strings
 
     # Default language settings. language_map is used to detect a source
     # file or Extension target language, checking source filenames.
@@ -1002,11 +1003,19 @@
             basename = os.path.basename (basename)
         return os.path.join(output_dir, basename + (self.exe_extension or ''))
 
+    def _join_lib_types(self):
+        a = []
+        for lib_type in self.lib_types:
+            a.append('"%s"' % lib_type)
+        return ", ".join(a[:-1]) + " or " + a[-1]
+
     def library_filename(self, libname, lib_type='static',     # or 'shared'
                          strip_dir=0, output_dir=''):
         assert output_dir is not None
-        if lib_type not in ("static", "shared", "dylib"):
-            raise ValueError, "'lib_type' must be \"static\", \"shared\" or \"dylib\""
+        assert "static" in self.lib_types
+        assert "shared" in self.lib_types
+        if lib_type not in self.lib_types:
+            raise ValueError, "'lib_type' must be %s" % self._join_lib_types()
         fmt = getattr(self, lib_type + "_lib_format")
         ext = getattr(self, lib_type + "_lib_extension")
 
Index: Lib/distutils/unixccompiler.py
===================================================================
--- Lib/distutils/unixccompiler.py	(revision 66567)
+++ Lib/distutils/unixccompiler.py	(working copy)
@@ -137,8 +137,23 @@
     obj_extension = ".o"
     static_lib_extension = ".a"
     shared_lib_extension = ".so"
-    dylib_lib_extension = ".dylib"
-    static_lib_format = shared_lib_format = dylib_lib_format = "lib%s%s"
+    static_lib_format = shared_lib_format = "lib%s%s"
+
+    # We're second-guessing the linker here, with not much hard
+    # data to go on: GCC seems to prefer the shared library, so I'm
+    # assuming that *all* Unix C compilers do.  And of course I'm
+    # ignoring even GCC's "-static" option.  So sue me.
+
+    lib_types = ["shared", "static"]
+    if sys.platform[:6] == "darwin":
+        lib_types.insert(0, "dylib")
+        dylib_lib_extension = ".dylib"
+        dylib_lib_format = "lib%s%s"
+    elif sys.platform == "cygwin":
+        lib_types.insert(0, "implib")
+        implib_lib_extension = ".dll.a"
+        implib_lib_format = "lib%s%s"
+
     if sys.platform == "cygwin":
         exe_extension = ".exe"
 
@@ -296,24 +311,12 @@
         return "-l" + lib
 
     def find_library_file(self, dirs, lib, debug=0):
-        shared_f = self.library_filename(lib, lib_type='shared')
-        dylib_f = self.library_filename(lib, lib_type='dylib')
-        static_f = self.library_filename(lib, lib_type='static')
+        for lib_type in self.lib_types:
+            filename = self.library_filename(lib, lib_type=lib_type)
+            for dir in dirs:
+                path = os.path.join(dir, filename)
+                if os.path.exists(path):
+                    return path
 
-        for dir in dirs:
-            shared = os.path.join(dir, shared_f)
-            dylib = os.path.join(dir, dylib_f)
-            static = os.path.join(dir, static_f)
-            # We're second-guessing the linker here, with not much hard
-            # data to go on: GCC seems to prefer the shared library, so I'm
-            # assuming that *all* Unix C compilers do.  And of course I'm
-            # ignoring even GCC's "-static" option.  So sue me.
-            if os.path.exists(dylib):
-                return dylib
-            elif os.path.exists(shared):
-                return shared
-            elif os.path.exists(static):
-                return static
-
         # Oops, didn't find it in *any* of 'dirs'
         return None