0000891618-01-000014 S-4/A 2 20010108 CISCO SYSTEMS INC 0000858877 3576 770059951 CA 0731 S-4/A 33 333-51288 1503770 170 W TASMAN DR SAN JOSE CA 95134-1706 4085264000 225 WEST TASMAN DR SAN JOSE CA 95134-1706 S-4/A 1 f67431a2s-4a.txt AMENDMENT NO. 2 TO FORM S-4 EX-5.1 2 f67431a2ex5-1.txt EXHIBIT 5.1