diff --git a/pp/transport.py b/pp/transport.py
index b127c3a..0897fea 100644
--- a/pp/transport.py
+++ b/pp/transport.py
@@ -121,7 +121,7 @@ class PipeTransport(Transport):
     def __init__(self, r, w):
         self.scache = {}
         self.exiting = False
-        if isinstance(r, types.FileType) and isinstance(w, types.FileType):
+        if hasattr(r, 'read') and hasattr(w, 'write'):
             self.r = r
             self.w = w
         else:
diff --git a/ppft/transport.py b/ppft/transport.py
index 9489487..07b9b2c 100644
--- a/ppft/transport.py
+++ b/ppft/transport.py
@@ -135,7 +135,7 @@ def __init__(self, r, w):
        #open('/tmp/pp.debug', 'a+').write(repr((r,w))+'\n')
         self.scache = {}
         self.exiting = False
-        if isinstance(r, ppc.file) and isinstance(w, ppc.file):
+        if hasattr(r, 'read') and hasattr(w, 'write'):
             self.r = r
             self.w = w
         else:
@@ -158,7 +158,7 @@ def __init__(self, r, w):
     def send(self, msg):
        #l = len(ppc.b_(msg)) if (self.has_wb or self.w.mode == 'wb') else len(ppc.str_(msg))
        #open('/tmp/pp.debug', 'a+').write(repr(('s', l, self.w, msg))+'\n')
-        if self.has_wb or self.w.mode == 'wb':
+        if self.has_wb or (hasattr(self.w, 'mode') and self.w.mode == 'rb'):
             msg = ppc.b_(msg)
             self.wb.write(struct.pack("!Q", len(msg)))
             self.w.flush()
@@ -173,7 +173,7 @@ def receive(self, preprocess=None):
         e_size = struct.calcsize("!Q") # 8
         c_size = struct.calcsize("!c") # 1
         r_size = 0
-        stub = ppc.b_("") if (self.has_rb or self.r.mode == 'rb') else ""
+        stub = ppc.b_("") if (self.has_rb or (hasattr(self.r, 'mode') and self.r.mode == 'rb')) else ""
         data = stub
         while r_size < e_size:
             msg = self.rb.read(e_size-r_size)
diff --git a/setup.py b/setup.py
index 8e054d4..896d1e7 100755
--- a/setup.py
+++ b/setup.py
@@ -25,7 +25,7 @@
 stable_version = '1.6.6.1'
 target_version = '1.6.6.2'
 is_release = stable_version == target_version
-VERSION = stable_version if is_release else target_version + '.dev0'
+VERSION = stable_version if is_release else target_version + '.dev1'
 # os.chdir(pkgdir)
 # sys.path.insert(0, '.')
 # from ppcommon import __version__ as VERSION