WordPress MU

I`ve done all the steps in the readme except the ones with the php.ini editing because i use a hosting server and i dont have access to that.
So i get two error message :
Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator, webmaster@thedomain.com and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

Additionally, a 500 Internal Server Error error was encountered while trying to use an ErrorDocument to handle the request.

or this one

No WPMU site defined on this host. If you are the owner of this site, please check Debugging WPMU for further assistance.

The WPMU installation is not on the root directory but in a subdomain.
The first error comes when, i give the directory in which the WPMU installion is, write permissions.
Can anyone help me please?

I saw some users commenting that not messing with the config-sample.php file should make it work but for me it gives an error : Warning: constant() [function.constant]: Couldn't find constant VHOST in /home/lamisto/public_html/wpmu/wpmu-settings.php on line 33
No WPMU site defined on this host. If you are the owner of this site, please check Debugging WPMU for further assistance.

Well, first of all, looks like you didn't set up wildcard DNS and Apache server alias.
Second thing, check your error log and see where problems come from.
Posting error messages from server error log here might definitely help :)

well where do i have to set that because i have absolutely no idea.

Try reading the readme file included with the zip.

In the <VirtualHost> section of the config file for your host there
will be a line defining the hostname.
I really don`t know where this file is.

You're on a shared host aren't you?

Yes i am thats why im saying that i don`t know where to change that.

You should contact your hoster and ask them to do this for you.

I am getting the same error for my server but than i have tried it, by adding sub domain and it's work for me so try for it once and check it again.

That's not the way you do it as depending on what software you;re running, when you create that subdomain, a subdirectory may also be created and that's going to cause problems.

The method in the readme file is the method you need to use.

Im hosting on my own server and when i get done doing what it tells me to do it gives me my password and username then i click on the login and when it redirects me i get this message every time and i am using Apache and i enabled the mod_rewrite can anyone help me there