Hola amigos, yo también tengo el mismo problema (cargar index.html y luego index.php) pero tengo instalado el mambo 4.5.2

Estoy con dolor de cabeza de tanto pensar

Aqui les posteo el codigo de index.php a ver que se puede hacer:

<?php
/**
* @version $Id: index.php,v 1.9 2005/02/16 02:03:33 eddieajau Exp $
* @package Mambo
* @copyright (C) 2000 - 2005 Miro International Pty Ltd
* @license http://www.gnu.org/copyleft/gpl.html GNU/GPL
* Mambo is Free Software
*/

/** Set flag that this is a parent file */

// cargar inicio html antes de php



define( '_VALID_MOS', 1 );

// checks for configuration file, if none found loads installation page
if ( !file_exists( 'configuration.php' ) || filesize( 'configuration.php' ) < 10 ) {
header( 'Location: installation/index.php' );
exit();
}

include_once( 'globals.php' );
require_once( 'configuration.php' );

// displays offline page
if ( $mosConfig_offline == 1 ){
include( 'offline.php' );
exit();
}

require_once( 'includes/mambo.php' );
if (file_exists( 'components/com_sef/sef.php' )) {
require_once( 'components/com_sef/sef.php' );
} else {
require_once( 'includes/sef.php' );
}
require_once( 'includes/frontend.php' );

/*
Installation sub folder check, removed for work with CVS*/
if (file_exists( 'installation/index.php' )) {
include ('offline.php');
exit();
}
/**/
/** retrieve some expected url (or form) arguments */
$option = trim( strtolower( mosGetParam( $_REQUEST, 'option' ) ) );
$Itemid = intval( mosGetParam( $_REQUEST, 'Itemid', null ) );
$database = new database( $mosConfig_host, $mosConfig_user, $mosConfig_password, $mosConfig_db, $mosConfig_dbprefix );
$database->debug( $mosConfig_debug );
$acl = new gacl_api();

if ($option == '') {
if ($Itemid) {
$query = "SELECT id, link"
. "\n FROM #__menu"
. "\n WHERE menutype='mainmenu'"
. "\n AND id = '$Itemid'"
. "\n AND published = '1'"
;
$database->setQuery( $query );
} else {
$query = "SELECT id, link"
. "\n FROM #__menu"
. "\n WHERE menutype='mainmenu' AND published='1'"
. "\n ORDER BY parent, ordering LIMIT 1"
;
$database->setQuery( $query );
}
$menu = new mosMenu( $database );
if ($database->loadObject( $menu )) {
$Itemid = $menu->id;
}
$link = $menu->link;
if (($pos = strpos( $link, '?' )) !== false) {
$link = substr( $link, $pos+1 ). '&Itemid='.$Itemid;
}
parse_str( $link, $temp );
/** this is a patch, need to rework when globals are handled better */
foreach ($temp as $k=>$v) {
$GLOBALS[$k] = $v;
$_REQUEST[$k] = $v;
if ($k == 'option') {
$option = $v;
}
}
}

/** do we have a valid Itemid yet?? */
if ( $Itemid === null ) {
/** Nope, just use the homepage then. */
$query = "SELECT id"
. "\n FROM #__menu"
. "\n WHERE menutype='mainmenu'"
. "\n AND published='1'"
. "\n ORDER BY parent, ordering"
. "\n LIMIT 1"
;
$database->setQuery( $query );
$Itemid = $database->loadResult();
}

/** patch to lessen the impact on templates */
if ($option == 'search') {
$option = 'com_search';
}

/** mainframe is an API workhorse, lots of 'core' interaction routines */
$mainframe = new mosMainFrame( $database, $option, '.' );
$mainframe->initSession();

// loads english language file by default
if ( $mosConfig_lang == '' ) {
$mosConfig_lang = 'english';
}
include_once ( 'language/'.$mosConfig_lang.'.php' );

// frontend login & logout controls
$return = mosGetParam( $_REQUEST, 'return', NULL );
$message = mosGetParam( $_POST, 'message', 0 );
if ($option == "login") {
$mainframe->login();

// JS Popup message
if ( $message ) {
?>
<script>
<!--//
alert( "<?php echo _LOGIN_SUCCESS; ?>" );
//-->
</script>
<?php
}

if ($return) {
mosRedirect( $return );
} else {
mosRedirect( 'index.php' );
}

} else if ($option == "logout") {
$mainframe->logout();

// JS Popup message
if ( $message ) {
?>
<script>
<!--//
alert( "<?php echo _LOGOUT_SUCCESS; ?>" );
//-->
</script>
<?php
}

if ($return) {
mosRedirect( $return );
} else {
mosRedirect( 'index.php' );
}
}

/** get the information about the current user from the sessions table */
$my = $mainframe->getUser();

/** detect first visit */
$mainframe->detect();

$gid = intval( $my->gid );

// gets template for page
$cur_template = $mainframe->getTemplate();
/** temp fix - this feature is currently disabled */

/** @global A places to store information from processing of the component */
$_MOS_OPTION = array();

// precapture the output of the component
require_once( $mosConfig_absolute_path . '/editor/editor.php' );

ob_start();
if ($path = $mainframe->getPath( 'front' )) {
$task = mosGetParam( $_REQUEST, 'task', '' );
$ret = mosMenuCheck( $Itemid, $option, $task, $gid );
if ($ret) {
require_once( $path );
} else {
mosNotAuth();
}
} else {
echo _NOT_EXIST;
}
$_MOS_OPTION['buffer'] = ob_get_contents();
ob_end_clean();

initGzip();

header( 'Expires: Mon, 26 Jul 1997 05:00:00 GMT' );
header( 'Last-Modified: ' . gmdate( 'D, d M Y H:i:s' ) . ' GMT' );
header( 'Cache-Control: no-store, no-cache, must-revalidate' );
header( 'Cache-Control: post-check=0, pre-check=0', false );
header( 'Pragma: no-cache' );

// loads template file
if ( !file_exists( 'templates/'. $cur_template .'/index.php' ) ) {
echo _TEMPLATE_WARN . $cur_template;
} else {
require_once( 'templates/'. $cur_template .'/index.php' );
echo "<!-- ".time()." -->";
}

// displays queries performed for page
if ($mosConfig_debug) {
echo $database->_ticker . ' queries executed';
echo '<pre>';
foreach ($database->_log as $k=>$sql) {
echo $k+1 . "\n" . $sql . '<hr />';
}
}

doGzip();
?>