List view problem! lines that are supposed to be helping arent there

the lines that go underneath each and every song as well as the lines that seperate the title from time and artist and genre... are all gone.

i have already tried -trashing the prefs file
-repairing itunes
-removing and reinstalling itunes
-and gone through all the prefernces and help file i could ever think about seeing

i give up .. i need help. anyone have a similar problem?