[TYPO3-ect] Smarty: Which configuration to set?

[Ismaël Bidau]

I use smarty in BE for some dev.

What I do :

// Include the smarty class 
require_once(t3lib_extMgm::extPath('smarty').'class.tx_smarty.php');	
// Create a New instance of smarty
$localconf = array(
	'compile_dir' => '../../../../typo3temp/smarty_compile',
	'template_dir' => 'EXT:intervenant/contrat'
);
$this->smarty = tx_smarty::smarty($localconf);

But I have a warning

Warning: Invalid argument supplied for foreach() in 
/Users/bidau/Sites/www.ensci.com/typo3conf/ext/smarty/class.tx_smarty.php 
on line 81

Perhaps $arr is not an array the first time it's use, because I use it 
in BE ?

Ismaël BIDAU