diff --git a/iptools/__init__.py b/iptools/__init__.py
index 384fed1..414c93f 100644
--- a/iptools/__init__.py
+++ b/iptools/__init__.py
@@ -407,7 +407,7 @@ class IpRangeList (object):
     :type \*args: list of str and/or tuple
     """
     def __init__(self, *args):
-        self.ips = tuple(map(IpRange, args))
+        self.ips = tuple([IpRange(arg) for arg in args])
     #end __init__
 
     def __repr__(self):
diff --git a/iptools/ipv4.py b/iptools/ipv4.py
index 5696e7d..6280ee9 100644
--- a/iptools/ipv4.py
+++ b/iptools/ipv4.py
@@ -343,7 +343,7 @@ def validate_subnet(s):
     """
     if isinstance(s, basestring):
         if '/' in s:
-            start, mask = s.split('/', 2)
+            start, mask = s.split('/', 1)
             return validate_ip(start) and validate_netmask(mask)
         else:
             return False