Straight Line Magnetism

Hello.

I have recently upgraded to version 7.2 and quickly discovered that lines are no longer magnetic. The end and centre points are, but I could always snap other items to any point on a straight line. For example, if I draw an elipse and a vertical line (to represent a centre line), I would be able to drag the elipse and snap it's centre point anywhere along the line. Now, I must either snap the elipse to an end point and shift drag it to the desired location (no good if the line is not aligned to the grid), or draw a perpendicular line and snap the elipse to the end point of the perpendicular line. I have also installed this copy on to a new machine, so have I missed a setting somewhere or has this function been removed?

Thanks.