Update login fail

Hi,

I'm trying to update my Observium professional edidtion and, after input the user and password requested on the process, the system is requesting it again:

svn update --username partners@under.com.br
Updating '.':
Authentication realm: <http://svn.observium.org:80> Observium Professional Repository
Password for 'partners@under.com.br':
Authentication realm: <http://svn.observium.org:80> Observium Professional Repository
Username:

I'm able to login on the website with this user and password.

Any tips?