Fixed error when one of the HTTP headers contains 'unknown' instead of an IP address.
Fixed error when one of the HTTP headers contains 'unknown' instead of an IP address.


Former-commit-id: e5e5646926275ba675495d64073f86fec71ae812
acliss19xx/concrete5,deek87/concrete5,KorvinSzanto/concrete5,rikzuiderlicht/concrete5,MrKarlDilkington/concrete5,haeflimi/concrete5,concrete5/concrete5,mlocati/concrete5,acliss19xx/concrete5,KorvinSzanto/concrete5,hissy/concrete5,concrete5/concrete5,olsgreen/concrete5,olsgreen/concrete5,deek87/concrete5,jaromirdalecky/concrete5,a3020/concrete5,mlocati/concrete5,mainio/concrete5,MrKarlDilkington/concrete5,rikzuiderlicht/concrete5,biplobice/concrete5,hissy/concrete5,olsgreen/concrete5,deek87/concrete5,triplei/concrete5-8,mlocati/concrete5,acliss19xx/concrete5,hissy/concrete5,biplobice/concrete5,a3020/concrete5,mlocati/concrete5,concrete5/concrete5,jaromirdalecky/concrete5,jaromirdalecky/concrete5,hissy/concrete5,mainio/concrete5,concrete5/concrete5,biplobice/concrete5,haeflimi/concrete5,haeflimi/concrete5,triplei/concrete5-8,jaromirdalecky/concrete5,rikzuiderlicht/concrete5,mainio/concrete5,KorvinSzanto/concrete5,triplei/concrete5-8,biplobice/concrete5,deek87/concrete5,MrKarlDilkington/concrete5,haeflimi/concrete5