Labtec USB webcam problem

I'm running Lubuntu 12.10 , and I have a Labtec USB webcam. Ubuntu applications (like 'guvcview') recognize my webcam, and display the image properly. Despite this fact, Matlab's 2012a 'imaqtool' doesn't find any webcam.'imaqhwinfo' finds, however, 'dcam' and 'linuxvideo', but neither of them work with 'videoinput'.