Line renders its label illegible when "Fill" is off
 

When a black line crosses its label with the text "Fill" turned off, a few letters of text become illegible where they intersect the line. (I am using a background color and do not wish to have a white box background around the text.) Is there any workaround for this problem/bug, (other than breaking the line into two segments where it intersects the text)? I have tried turning text "Fill" on with the fill color the same as the background color, but unfortunately this does not hide the portion of the black line that intersects the text even after moving the label in front of the line. One would hope that there would be more intelligence built into the line drawing code to prevent this problem.

OmniGraffle Pro version 4.2.3