Addres Family not supported by protocol

hi,


I have proxy configured in a rb 433AH web proxy is enabled for http filtering. I upgraded routerboard version and im having a problem: with some frecuency proxy prompts this message “address family not supported by protocol”.

Searching in internet it seems is caused by ipv6 protocol. In my hosts ( ubuntu 14.04) and routerboard ipv6 protocol is disabled.

some help would be very useful.