There is a problem creating a user with a character that is not in the 7-bit ASCII list inside the login field. For example accented characters in spanish produce the problem. You can create the user the problem arises once you try to access the form of the user again, the following error appears :
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File "/usr/lib/python2.6/site-packages/openerp-7.0_20130716_231027-py2.6.egg/openerp/addons/auth_signup/res_users.py", line 87, in _get_signup_url_for_action res[partner.id] = urljoin(base_url, "?%s#%s" % (urlencode(query), urlencode(fragment))) File "/usr/lib/python2.6/urllib.py", line 1269, in urlencode v = quote_plus(str(v)) UnicodeEncodeError: 'ascii' codec can't encode character u'\xa1' in position 0: ordinal not in range(128)
This is a common problem for python. Anyways it's better if you avoid non utf-8 characters.