On almost every macpherson (sp?) strut car, as soon as outside of the lower A or control arm gets above perpendicular, any additional lowering will cause an increase in camber. Anywhere below perpendicular, camber decreases as the car is lowered. This is basic geometry. There is a drawing on Debbie's white board if anybody wants to see it...
I could try in paint, but I am no Sybir...
This is the reason slamming a macpherson strut car is often not the greatest thing for handling. the lower it is, the faster things go positive as the suspension compresses.
Otherwise, everything Scott said...