Many people have reported having problems logging in to serweb after installation.
I had the problem myself, and after some inspection of the html/admin/index.php file, the following lines game me a hint:
if ($config->clear_text_pw) { $q="select phplib_id from ". $config->table_subscriber. " where username='".addslashes($uname)."' and password='".addslashes($passw)."' and perms='admin' and domain='".addslashes($config->realm)."'";
So, the SELECT statament wants to match the 'username', 'password', 'perms' and 'domain' fields from the 'subscriber' table.
In your html/config.php file, comment-out the regex replace and type your domain exactly as it is in your db. e.g:
/* your domain name */ # $this->realm=$this->domainname=$this->default_domain= ereg_replace( "(www.|sip.)?(.*)", "\2", $_SERVER['SERVER_NAME']);
$this->realm="mydomain.com";
Hope this helps.
cv