Found it the problem:
on the page:
http://wiki.openwrt.org/OpenWrtNVRAM at the end of section 1
there is a remark:
Don't set *_gateway more than once, or use *_proto=dhcp on more than one interface, or you'll find yourself with multiple default routes inserted which is probably not what you want.
I checked it on my router and:
root@vostok:~$ nvram show | grep _gateway
lan_gateway=192.168.1.1
wan_gateway=86.105.127.1
and the misconfiguration was introduced on the webif (Webif2) by setting on the page
Network -> WAN-LAN -> LAN Configuration, by setting 192.168.1.1 for Default Gateway.
Removed this and the wrong entry disappeared. and the command now shows:
root@vostok:~$ nvram show | grep _gateway
lan_gateway=
wan_gateway=86.105.127.1
