[OS X TeX] weird rule behavior

[Roberto Avanzi]

I also had this problem - that of disappearing lines (hrules and  
vrules).

This morning I decided to take out my OS X leopard installation disk  
and force reinstall the HP printer drivers using Pacifist.  Only the  
HP ones.   Nothing else.

A document, that printed incorrectly a few minutes before, now prints  
perfectly on an HP Laserjet 4005c.

Of course Software Update now reminds me to update the HP printer  
drivers, but I am not a fool ;)

  Roberto