diff --git a/IPython/platutils.py b/IPython/platutils.py
index 197d489..561e68d 100644
--- a/IPython/platutils.py
+++ b/IPython/platutils.py
@@ -88,6 +88,14 @@ def find_cmd(cmd):
         raise FindCmdError('command could not be found: %s' % cmd)
     return path
 
+def get_long_path_name(path):
+    """Expand a path into its long form.
+
+    On Windows this expands any ~ in the paths. On other platforms, it is
+    a null operation.
+    """
+    return _platutils.get_long_path_name(path)
+
 #-----------------------------------------------------------------------------
 # Deprecated functions
 #-----------------------------------------------------------------------------
diff --git a/IPython/platutils_dummy.py b/IPython/platutils_dummy.py
index 35aa5a0..0cb8965 100644
--- a/IPython/platutils_dummy.py
+++ b/IPython/platutils_dummy.py
@@ -27,3 +27,7 @@ def set_term_title(*args,**kw):
 def find_cmd(cmd):
     """Find the full path to a command using which."""
     return os.popen('which %s' % cmd).read().strip()
+
+def get_long_path_name(path):
+    """Dummy no-op."""
+    return path
diff --git a/IPython/platutils_posix.py b/IPython/platutils_posix.py
index d0700a2..b306479 100644
--- a/IPython/platutils_posix.py
+++ b/IPython/platutils_posix.py
@@ -34,3 +34,7 @@ else:
 def find_cmd(cmd):
     """Find the full path to a command using which."""
     return os.popen('which %s' % cmd).read().strip()
+
+def get_long_path_name(path):
+    """Dummy no-op."""
+    return path
diff --git a/IPython/platutils_win32.py b/IPython/platutils_win32.py
index 10fe9b9..66ae27f 100644
--- a/IPython/platutils_win32.py
+++ b/IPython/platutils_win32.py
@@ -54,3 +54,29 @@ def find_cmd(cmd):
         except:
             (path, offset) = win32api.SearchPath(os.environ['PATH'],cmd + '.bat')
     return path
+
+
+def get_long_path_name(path):
+    """Get a long path name (expand ~) on Windows using ctypes.
+
+    Examples
+    --------
+
+    >>> get_long_path_name('c:\\docume~1')
+    u'c:\\\\Documents and Settings'
+
+    """
+    try:
+        import ctypes
+    except ImportError:
+        raise ImportError('you need to have ctypes installed for this to work')
+    _GetLongPathName = ctypes.windll.kernel32.GetLongPathNameW
+    _GetLongPathName.argtypes = [ctypes.c_wchar_p, ctypes.c_wchar_p,
+        ctypes.c_uint ]
+
+    buf = ctypes.create_unicode_buffer(260)
+    rv = _GetLongPathName(path, buf, 260)
+    if rv == 0 or rv > 260:
+        return path
+    else:
+        return buf.value
diff --git a/IPython/testing/iptest.py b/IPython/testing/iptest.py
index bba6d6a..22b7496 100644
--- a/IPython/testing/iptest.py
+++ b/IPython/testing/iptest.py
@@ -213,6 +213,13 @@ def make_runners():
     if have_pexpect:
         top_mod.append('irunner.py')
 
+    if sys.platform == 'win32':
+        top_mod.append('platutils_win32.py')
+    elif os.name == 'posix':
+        top_mod.append('platutils_posix.py')
+    else:
+        top_mod.append('platutils_dummy.py')
+
     # These are tested by nose, so skip IPython.kernel
     top_pack = ['config','Extensions','frontend',
                 'testing','tests','tools','UserConfig']
diff --git a/IPython/tests/test_magic.py b/IPython/tests/test_magic.py
index 6815879..e090ea2 100644
--- a/IPython/tests/test_magic.py
+++ b/IPython/tests/test_magic.py
@@ -10,7 +10,7 @@ import types
 
 import nose.tools as nt
 
-from IPython.platutils import find_cmd
+from IPython.platutils import find_cmd, get_long_path_name
 from IPython.testing import decorators as dec
 from IPython.testing import tools as tt
 
@@ -206,14 +206,16 @@ class TestMagicRun(object):
         self.tmpfile = f
 
     def run_tmpfile(self):
+        # This fails on Windows if self.tmpfile.name has spaces or "~" in it.
+        # See below and ticket https://bugs.launchpad.net/bugs/366353
         _ip.magic('run %s' % self.tmpfile.name)
 
     # See https://bugs.launchpad.net/bugs/366353
     @dec.skip_if_not_win32
     def test_run_tempfile_path(self):
-        # self.run_tmpfile() # This is what triggers the error!
         tt.assert_equals(True,False,"%run doesn't work with tempfile paths on win32.")
 
+    # See https://bugs.launchpad.net/bugs/366353
     @dec.skip_win32
     def test_builtins_id(self):
         """Check that %run doesn't damage __builtins__ """
@@ -224,6 +226,7 @@ class TestMagicRun(object):
         bid2 = id(_ip.user_ns['__builtins__'])
         tt.assert_equals(bid1, bid2)
 
+    # See https://bugs.launchpad.net/bugs/366353
     @dec.skip_win32
     def test_builtins_type(self):
         """Check that the type of __builtins__ doesn't change with %run.
@@ -235,6 +238,7 @@ class TestMagicRun(object):
         self.run_tmpfile()
         tt.assert_equals(type(_ip.user_ns['__builtins__']),type(sys))
 
+    # See https://bugs.launchpad.net/bugs/366353
     @dec.skip_win32
     def test_prompts(self):
         """Test that prompts correctly generate after %run"""
diff --git a/IPython/tests/test_platutils.py b/IPython/tests/test_platutils.py
index ca2989e..36d189f 100644
--- a/IPython/tests/test_platutils.py
+++ b/IPython/tests/test_platutils.py
@@ -20,7 +20,7 @@ import sys
 
 import nose.tools as nt
 
-from IPython.platutils import find_cmd, FindCmdError
+from IPython.platutils import find_cmd, FindCmdError, get_long_path_name
 from IPython.testing import decorators as dec
 
 #-----------------------------------------------------------------------------
@@ -46,3 +46,14 @@ def test_find_cmd():
 def test_find_cmd_fail():
     """Make sure that FindCmdError is raised if we can't find the cmd."""
     nt.assert_raises(FindCmdError,find_cmd,'asdfasdf')
+
+@dec.skip_if_not_win32
+def test_get_long_path_name_win32():
+    p = get_long_path_name('c:\\docume~1')
+    nt.assert_equals(p,u'c:\\Documents and Settings') 
+   
+@dec.skip_win32
+def test_get_long_path_name():
+    p = get_long_path_name('/usr/local')
+    nt.assert_equals(p,'/usr/local')
+