Regarding my comment above, I tried Benjamin's suggestion to install eclipse-plugin-cvs, which led me to learn that I also needed to install these packages via apt-get too: eclipse-jdt eclipse-pde Then new software installation worked! Thanks for the suggestion.
https://bugs.launchpad.net/ubuntu/+source/eclipse/+bug/454819

Bug #454819 in eclipse (Ubuntu): “The artifact file for osgi.bundle,org.eclipse.update.core.linux,3.2.100.v20081008 was not found”
作成: 2010年06月14日 04時46分 / 更新: 2010年06月14日 07時51分

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