Yes, you can change it to a white cursor in the KDE Control Center, but it sometimes doesn't work and could mess up X if you're not careful. However, XFree86 v4.3 supports a new feature that allows you to theme your cursors. It supports shadows, translucency, etc. Check KDE-Look.org for more of these themes when 4.3 is released (it is tagged for the 27th of Feb).
In the meantime, there is a really nice theme in development here:
http://www.kde-look.org/content/show.php?content=4805
