CWebDavFile::RegisterVirtualIOCompatibility

function RegisterVirtualIOCompatibility($baseDir='')
{
	static $IOCompartible = 'BX_IO_Compartible';
	if (defined($IOCompartible))
		return false;

	define($IOCompartible, 'Y');
	AddEventHandler('main', 'BXVirtualIO_ConvertCharset', array($this, 'VirtualIO_ConvertCharset'));

	return true;
}