non www cannot access other page .htaccess

[robert_gsfame]

i have this

 

<IfModule mod_rewrite.c>

Options +FollowSymLinks

Options +Indexes

RewriteEngine On

RewriteBase /

RewriteCond %{HTTP_HOST} !www\.mydomain\.com\.th$ [NC]

RewriteCond %{HTTP_HOST} ^([a-z0-9-]+)\.mydomain\.com\.th [NC]

RewriteRule (.*) mypage.php?user=%1 [L]

RewriteCond %{HTTP_HOST} ([^.]+)\.mydomain\.com\.th

</IfModule>

ErrorDocument 404 /error.html

 

when i access www.user.mydomain.com.th everything goes normal including all links can be accessed but when i write http://user.mydomain.com.th and try to access the provided link, i didnt get redirected to the specified page.

 

some script for .htaccess must be missing, can anyone help?

 

thx