Problems with "launch at startup" script

[rastersoft <raster rastersoft com>]

Hi all:

I'm using gnome shell since version 3.2. I also have a logitech mouse 
with zillions of buttons, and I have the problem that I hate to have the 
third button in the mouse wheel, so I've been using xmodmap in a startup 
script to put it in another button. The specific script is:

#!/bin/bash

xmodmap -e "pointer = 1 13 3 4 5 6 7 8 9 10 11 12 2"

Until gnome shell 3.6 it worked like a charm, but starting with gnome 
shell 3.8 it started to fail in some boots, but in others it worked 
fine. Now, with gnome shell 3.10 it doesn't work at startup, and I must 
run it manually.

I checked the output of the script during launch (redirecting both 
stdout and stderr to a file) and the script runs fine (no errors), but 
the mouse buttons aren't changed. I also tried to remove it from the 
startup programs just in case the X server remembered the new button 
order, and each time I boot the script was changing it to the standard 
order, but no: the X server resets each time I reboot the computer.

I also tried to add a sleep in the script, just in case the problem was 
only if it was launched before gnome shell fully loaded, but also 
without luck.

So... what can I do?

Thanks.

--
Nos leemos
                         RASTER    (Linux user #228804)
raster rastersoft com              http://www.rastersoft.com