regex match.groupdict() returns wrong values

Binary package hint: ironpython

match object's groupdict() returns wrong key & value combinations.
Attached is a test case to reproduce the problem.

Works:
IronPython 2.6 for .NET2.0 SP1 on Windows XP SP3 32bit
CPython2.6 on Ubuntu 10.04LTS i386
CPython2.6 on Ubuntu 10.04LTS x86_64

Does'nt work:
ironpython 2.6~beta2-2 on Ubuntu 10.04.1 LTS i386
ironpython 2.6~beta2-2 on Ubuntu 10.04.1 LTS x86_64

#Test case
import re
p = re.compile(r'''
             (?P<name>[\w\+]+)://
             (?:
                 (?P<username>[^:/]*)
                 (?::(?P<password>[^/]*))?
             @)?
             (?:
                 (?P<host>[^/:]*)
                 (?::(?P<port>[^/]*))?
             )?
             (?:/(?P<database>.*))?
             '''
             , re.X)

m = p.match('http://user:pass@localhost:666/xyz')
print m.groups()
print m.groupdict()

# expected result. dict keys in arbitrary order
('http', 'user', 'pass', 'localhost', '666', 'xyz')
{'username': 'user', 'protocol': 'http', 'database': 'xyz', 'host': 'localhost', 'password': 'pass', 'port': '666'}

# results on ubuntu 10.04LTS i386/x86_64
('http', 'user', 'pass', 'localhost', '666', 'xyz')
{'username': 'http://user:pass@localhost:666/xyz', 'port': 'xyz', 'protocol': 'http', 'database': 'user', 'host': 'localhost', 'password': '666'}