Sorry for a mistake. I am using Red Hat 7.2 in AMD-64 machine, not FEDORA. Dr. Md. Nazrul Islam Associate Professor Department of Physics Bangladesh University of Engineering and Technology Dhaka-1000, Bangladesh http://www.buet.ac.bd/phy/nazrul.htm Phone: 880 2 966 5650 (PABX) FAX: 880 2 861 3026, 880 2 861 3046