After uploading project on my webserver I came up with this kind of error:
Parse error: syntax error, unexpected T_OBJECT_OPERATOR in path\to\project\web\index.php on line 12
which is this line:
sfContext::getInstance()->getController()->dispatch();
The problem was in PHP version set on webserver. So when I looked at check_configuration.php is saw that webserver is set for PHP4.
After changing into PHP5, everything went all right.