вот так конвертировал:
<?php
// Database info
include("conf_global.php");
$dbhost = $INFO['sql_host'];
$dbuser = $INFO['sql_user'];
$dbpass = $INFO['sql_pass'];
$dbname = $INFO['sql_database'];
//---------------
$dbconn = mysql_connect($dbhost, $dbuser, $dbpass) or die( mysql_error() );
$db = mysql_select_db($dbname) or die( mysql_error() );
$sql = "ALTER DATABASE `".$dbname."` DEFAULT CHARACTER SET utf8 COLLATE utf8_unicode_ci;n";
$exec_sql = 'SHOW TABLES';
$result = mysql_query($exec_sql) or die( mysql_error() );
while ( $row = mysql_fetch_row($result) )
{
$table = mysql_real_escape_string($row[0]);
$sql .= "ALTER TABLE `".$table."` DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci, CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci;n";
}
mysql_close($dbconn);
echo $sql;