I treated this error yesterday at Microsoft Forums, and I think it may occur easily for all administrator that do not use english domain controllers.
When you try to access Address List on OWA, you receive a message error like this:
Request Url: https://<server-ip-address>:443/owa/forms/premium/DirectoryView.aspx?ae=AddressList&t=Recipients&a=Pick
User host address: <ip-address>
EX Address: /o=XX/ou=GR/cn=RECIPIENTS/cn=SOMEONE
SMTP Address: <smtp-address>
OWA version: 8.0.605.16
This error may occur if the OWA client and Domain Controller do not have the same locale setting.
Microsoft has released a hotfix to fix it. You can check it out here: http://support.microsoft.com/default.aspx/kb/919166/en-us