Have you already tried the following ?
As root, type rmmod speedtch and launch the following script :
http://speedtouchconf.sourceforge.net/.
It will likely say something like you have no USB. Edit the script, comment the test :
# if [ -z "${USB_TYPE}" ]; then
# echo "No USB Bus found!" | tee -a $LOGFILE
# error=`expr $error + 2`
# fi
and relaunch.
It worked for me.