not able to change the agent password

Hi,

i installed the virtual appliance. When connecting via IP, i am not asked for a login because there is no passsword for the user admin by default. So i want to change the password for admin. But when i try to set a pw, i am asked for the old one, but there is none set. What is the problem? At the moment everyone can come per anonymous and do changes. Very bad securitysettings by default i think.