why don't you use the correct format as i had suggested here.. That is all..
give address in full.. like 192.168.0.1/255.255.255.0
I think squid don't understand that short notation like 24 or 32.. but i m not sure about it..
BTW.. Your this question is not so unique so i think you should ask that in earlier thread where you had asked about the time acl..