diff --git a/gunicorn/util.py b/gunicorn/util.py
index f472cf5a..4c0c0ea6 100644
--- a/gunicorn/util.py
+++ b/gunicorn/util.py
@@ -209,6 +209,8 @@ def is_ipv6(addr):
         socket.inet_pton(socket.AF_INET6, addr)
     except socket.error:  # not a valid address
         return False
+    except ValueError: # ipv6 not supported on this platform
+        return False
     return True