Awkward behaviour with USB mouse

[Pablo de Vicente <pvicentea@nexo.es>]

I am running woody + sid (for KDE) on a laptop with a touchpad and a USB 
connector. I have noticed that when I plug a wheel Logitech mouse to the USB 
connector the cursor behaves, sometimes (not constantly), in an unpredictable 
way for some KDE applications. This is most frequent when using kbabel ( I 
have real problems when translating big paragraphs because the cursor jumps 
forth, or the application moves some fields forth or back), less frecuent 
when using Kmail (for example), and very rare when I use konsole. I have not 
tried this with non-KDE applications.

 If I use this same mouse (with a USB to PS/2 interface) plugged into the 
PS/2 port the applications are rock stable and the cursor always behaves as 
it should. 

  Has somebody experienced this same behaviour?, Is this KDE related, X 
related, USB related or specific of my laptop?. Is this a known bug?. I am 
lost.

thanks,

Pablo de Vicente.