I have been following the unfolding saga of the "@2" pathogen with interest for some time now...
For those who might like to narrow the search for the cause>
A few weeks ago I created a Live USB (isohybrid) stick containing my old remaster of PCLOS 2009.1 (4Gig) including a bunch of games - SSam/CWolf/WC111/ etc...
This was based on KDE 3.5.10 & kernel 2.6.26.tex3. (I'm using it now... @@@@222222@@@@222)
There is no "@2" problem evident!!
This "@2" issue appears to be a KDE 4.X problem or a more recent 2.6.3+ kernel related instability.
>Steve

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I have today remastered a new build based on PCLOS 2010.12 + kernel 2.6.38.3-pclos1.bfs (KDE 4.6.2) and full updates + prefs...
Problem of X session restart on "2" & "@" keys on LiveUSB stick session no longer evident!Happy Days! 
>Steve
Edit> Not out of the woods yet! I got the session to crash....
