I've just hit the same problem I believe in the 5.7 distribution. In Eclipse, the .classpath file contains pointers to libraraies that don't exist in the distribution. For example the .classpath for the cxf-examples contains the following entries:
<classpathentry kind="lib" path="libs-runtime/commons-lang-2.4.jar"/>
<classpathentry kind="lib" path="libs-runtime/commons-logging-1.1.1.jar"/>
<classpathentry kind="lib" path="libs-runtime/cxf-api-2.1.2.jar"/>
the libs-runtime directory for the cxf example does not contain commons-lang-2.4.jar at all, does contain commons-logging-1.1.1.jar, and does not contain cxf-api-2.1.2.jar, but does contain cxf-api-2.3.1.jar.
Is the problem with the classpath file, or are there libraries missing from the distro?