Is there a way to prevent one user from changing info in profile?

I want to create one "DEMO" user that should have access to the member area but should not be able to change any info there - mainly not the info in the profile, should not be able to order products etc.

If that's not possible, I want to completely disallow login for this user.

Is there a way to do this without hacking the core code? Perhaps with some hooks?

Thanks for any ideas!

Tomas

Maybe disable the form if the demo user is logged in?
untested: (havent used a != in smarty before)
profile.html
{if $smarty.session._amember_user.login != "demo"}
<form name="signup" method="post" action="{$smarty.server.PHP_SELF|escape}">
</if}

David

"ne" works just fine (not equal), in case "!=" doesn't work...

Thanks guys, it worked

Tomas