The account renaming service (change account name) was discontinued on October 31, 2012 (Wednesday).
Users who have already renamed their accounts prior to October 31, 2012 will not be affected. They can continue using their current account names.
Instead of renaming the account, users can setup an email alias. An email alias is a forwarding email address which is easier for your email recipients to remember, e.g. "firstname.lastname@example.org". While the current email account name is limited to 8 characters, an email alias allows 9 to 32 characters with combination of letters, numbers and special characters "-", "." and "_".
Please note that an email alias is not another email account. Instead, it is an email address that forwards emails to your graduate.hku.hk email account. Therefore, the email alias cannot be used to login your email account where the account name is required.
To set up an email alias, please visit http://daaoweb.hku.hk/en/alumni/grademail_grad.htm