WordPress MU

all blogs will redirect if they are access with www after slash. http://sub-blog.mainblog.com works fine but http://www.sub-blog.mainblog.com will redirect to http://mainblog.com how to solve this?

Last time we saw this, the mu was installed as an addon domain within cpanel. You haven't done this, have you? It needs to be installed as the main domain within the account.

If not, maybe some server details and how you have it installed would be helpful.

done with it and it was working fine. just don't know what is going on on my sub blogs...

Hey, there's one...

@aeonscoop,
what do you mean?

until now can't get it to work..

Not sure what exactly you need to fix...

@VentureMaker, all my blogs http://sub-blog.mainblog.com will redirect to http://mainblog.com if you type in the browser like this http://www.sub-blog.mainblog.com

I want to know how to fix this.

First of all, do you have any extra stuff in .htaccess?
Later, get rid of www - make all domains and subdomains behave in a way that entering http://www.domain.com will go to http://domain.com
Different hosts have different tools to achieve this.

Make sure you have wildcard DNS set up properly, make sure your main domain does not have redirects, aliases, other things.

@VentureMaker,
here is my .htaccess
RewriteEngine On
RewriteBase /

#uploaded files
RewriteRule ^(.*/)?files/$ index.php [L]
RewriteCond %{REQUEST_URI} !.*wp-content/plugins.*
RewriteRule ^(.*/)?files/(.*) wp-content/blogs.php?file=$2 [L]

# add a trailing slash to /wp-admin
RewriteCond %{REQUEST_URI} ^.*/wp-admin$
RewriteRule ^(.+)$ $1/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule . - [L]
RewriteRule ^([_0-9a-zA-Z-]+/)?(wp-.*) $2 [L]
RewriteRule ^([_0-9a-zA-Z-]+/)?(.*\.php)$ $2 [L]
RewriteRule . index.php [L]

<IfModule mod_security.c>
<Files async-upload.php>
SecFilterEngine Off
SecFilterScanPOST Off
</Files>
</IfModule>

#<Directory /home/ilikeceb/public_html>
#AllowOverride FileInfo
#</Directory>
# compress all text & html:
#AddOutputFilterByType DEFLATE text/html text/plain text/xml

# Or, compress certain file types by extension:
<Files *.html>
#SetOutputFilter DEFLATE
</Files>
I have wild card DNS set up properly and I don't have any redirects, aliases etc...

What's your domain?

@VentureMaker
here is my domain: http://ilikecebu.com
sub-blogs:
http://ceburestaurants.ilikecebu.com
http://cebuano.ilikecebu.com
they will redirect to my main blog if i will put www after slash on the sub-blogs.