Sorry, but this article must be written in English.
I have buy an “Open DMX USB” from enttec. Under Windows it work with the driver downloadable from the site and it work with much program.
But… windows isn’t the way i write this article….
Under Linux i haven’t found any driver on the productor site.
Searching on the web (Thanks google) i have found a module for this controller on http://www.erwinrol.com/
On this page there are some information on the module and on the DMX standard.
The module can be downloadable from the site.
The new version of this module are bownsable from :
http://git.hbelightingsystems.com/?p=dmx_usb_module;a=summary
and can be download from here
git://git.hbelightingsystems.com/public/dmx_usb_module
The module make a device under /dev called /dev/dmx0 and can be writted to send a dmx channel.
I have make a program in C to interface to this module and a web gui.
From a web gui, 
you can select the number of channel DMX and a value that you want to assign. You can assign at DMX value [0-255] or at percent [0-100%] and the module make a conversion.
Can also select a large number of channel and exclude some.
Example: Click on
‘1’ ‘To’ ’10’ ‘-‘ ‘4’ ‘Full’ Make all channel from 1 to 10 exept channel 4 at Full.
Work under a Web interface make you to remote all the system on a single machine.
If you have a Linksys WRT54 you can connect the module on a USB port and use it as web server and connect to it with a remote device.
Personaly I use my notebook with Linux as access point, and with my palm I can put light on and off from the stage and check the illumination.
At about 1 week i put on-line the C source and the web page to make all work (i have a little problem to integrate 2 single page in a single page in php 🙂 )
The web interface is make more big to be simple to click the correct key with a touchscreen device.
I must say “Thank you very much” to Erwin both for the kernel module and for all the mail tha i have send him to understand the module and the dmx protocoll. This article is in English also for you 😉
Stefano
Well, I’ve been told to check my grammar but you should really check you english as a whole 🙂
(on a completely unrelated topic (no, not really) I’ve been quite busy, so I couldn’t integrate my work with yours… yet)