Improve barcode scanning on a low resolution camera (3.2MP) without auto focus

I have two phones, one has a 3.2MP camera, and the other has an 8MP camera. I downloaded the 'Barcode Scanner ' app on both phones, it works on the 8MP phone but the 3.2MP phone sometimes doesn't pick up any barcodes at all. Update: from the discussion in the comment thread, it seems the phone doesn't pick up barcodes because it doesn't have Auto Focus. Is there a way I can get around this?