mysqlnd and LOAD DATA INFILE

Hello, we recently updated our mysql client libs to mysql-5.5.13 and since it was impossible to rebuild PHP 5.2.x and PHP 5.3.x with this new mysql release, we rebuilt PHP with --with-mysql=mysqlnd and ---with-mysqli=mysqlnd. General mysql commands work fine, but one of our clients reported, that the command "LOAD DATA INFILE" isn't working any longer. As the setup of the mysql server hasn't changed and as on the webserver only PHP was rebuilt, I assume that the problem is in mysqlnd?! How does mysqlnd handle LOAD DATA INFILE? And if the problem is not in mysqlnd, what else could it be? Kind regards Marten