Squid ipv6 only

After install Squid, I check listening ports:
netstat -tulpn | grep 3128
tcp        0      0   :::3128             :::*           LISTEN      7798/(squid-1)

So, ipv6 is good, but me need a ipv4

vi /etc/squid/squid.conf
http_port 0.0.0.0:3128

Restart Squid and check again:

tcp        0      0   0.0.0.0:3128        :::*           LISTEN      7798/(squid-1)