Hi everyone, i have my samsung galaxy s1 i9000 unrooted. I want to upgrade it to android 4.0 (ICS), can someone help me please?

FIRMWARE: 3.4.5
BASEBAND VERSION: I9000XXJVS
KERNEL VERSION: 2.6.35.7-I9000XXJVS-CL565837 se.infra@SEP-73 #2
BUILD NUMBER: GINGERBREAD.XXJVS