Created attachment 623576 [details]
Unsatisfactory output produced by LaTeX.
I've added an attachment of the problematic output, produced with latex+dvips
on a vanilla install of openSuSE 13.2.
Observe how the problem shows up inconsistently depending on the font size.
Changing [12pt] in the preamble to e.g. [11pt] changes (but doesn't resolve)
the problematic output.