diff --git a/attributs.py b/attributs.py
index 66fe752..d1d58d4 100644
--- a/attributs.py
+++ b/attributs.py
@@ -384,12 +384,32 @@ class portAttr(Attr):
     optional = True
 
     def parse_value(self, port, ldif):
-        if int(port) <0 or int(port)> 65535:
-            raise ValueError("Port invalide: %s" % port)
-        self.value = int(port)
+        if ":" in port:
+            a,b = port.split(":", 1)
+            if a:
+                if int(a) <0 or int(a)> 65535:
+                    raise ValueError("Port invalide: %s" % port)
+            else:
+                a = 0
+            if b:
+                if int(a) <0 or int(a)> 65535:
+                    raise ValueError("Port invalide: %s" % port)
+            else:
+                b = 65535
+            self.value = [int(a), int(b)]
+        else:
+            if int(port) <0 or int(port)> 65535:
+                raise ValueError("Port invalide: %s" % port)
+            self.value = [int(port)]
 
     def __unicode__(self):
-        return unicode(self.value)
+        if len(self.value) > 1:
+            a, b = self.value
+            a = '' if a == 0 else str(a)
+            b = '' if b == 65535 else str(b)
+            return unicode('%s:%s' % (a, b))
+        else:
+            return unicode(self.value[0])
 
 
 class portTCPout(portAttr):