0000950149-01-500491 DEF 14A 1 20010518 20010416 SIMPSON MANUFACTURING CO INC /CA/ 0000920371 3420 943196943 DE 1231 DEF 14A 34 001-13429 1602716 4637 CHABOT DR STE 200 PLEASANTON CA 94588 5106099912 4637 CHABOT DR STE 200 PLEASANTON CA 94588 DEF 14A 1 f71405ddef14a.txt NOTICE AND PROXY STATEMENT