I've upgrated Kde 3.5.2 to kde 3.5.3
So The message in syslog disapear and kdm doesn't crash anymore.
tu upgrade, juts put these lines in "/etc/apt/sources.list":
deb http://kubuntu.org/packages/kde-353 dapper main
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kdm crash due to corrupted ~/.face.icon file
https://launchpad.net/bugs/37529