Description:
------------
When I run the example of PHP documentation
(http://fr2.php.net/manual/en/function.dio-tcsetattr.php), all is OK.
But when replace the baud rate value (9600) by a variable containing the
same value, I have a php warning :

Warning: dio_tcsetattr() [function.dio-tcsetattr]: invalid baud rate 0 in
/var/www/lampes.php on line 34

I verified by an "echo $var;", this variable isn't equal to 0 !

This is the same problem with the other attributes (bit, stop and parity).

Reproduce code:
---------------
...
$SPEED=9600;
echo $SPEED;

$fd = dio_open("/dev/ttyS0" , O_WRONLY | O_NOCTTY | O_NONBLOCK);
dio_tcsetattr($fd , array('baud' => $SPEED, 'bit' => 8 , 'stop' => 1 , 'parity' => 0));
...