hey wait... while looking through the X wacom source(to try and make a
quick fix for my problem) i noticed some interesting things.
on line 1372 of xf86Wacom.c, it reads
/* The stylus reports button 4 for the second side
* switch and button 4/5 for the eraser tip. We know
* how to choose when we come in proximity for the
* first time. If we are in proximity and button 4 then
* we have the eraser else we have the second side
it then goes through some things with proximity, might want to take a look
at this code to see how it handles things... i don't think that bug your
experiencing is all that odd, it looks to me that if the button1 is
pressed, a pressure is being read, so when it sees the button4 pressed, it
thinks its from the eraser and uses that.
because button4 and eraser tip are connected like it is, there may not be
a method of fixing this, except by making a work-around.
reading again, it might be that the problem is right here too... and it
might be very easy to fix.
well, hope i've helped