Apologies if this is a duplicate of Issue 70874, however it is difficult to tell because that issue is very terse and
anyway seems to apply to Netbeans 5.0.

There are two issues with the current codecoverage plugin.  The first is that simply closing and reopening the project
disables code coverage as of Netbeans 6.5.  The second is that the variable 'file.reference.emma.jar', which does not
appear anywhere I could locate in the Netbeans GUI, is overwritten with the location of the plugin's copy of emma.jar
(.netbeans/6.5/modules/ext/emma.jar) if changed.  This variable is defined by the codecoverage plugin in the
.../nbproject/private/private.properties file. If it is not changed, the Netbeans-generated build.xml, which is
otherwise fine, cannot run the tests unless the target platform also has the Netbeans codecoverage plugin installed in
the exact same location.

The only workaround I could find was to install an otherwise-unused copy of the Netbeans plugin on my hudson server so
that .../.netbeans/6.5/modules/ext.emma.jar could be loaded by the unit tests.  Otherwise, whenever a developer reopens
the project, the file .../nbproject/private/private.properties is automatically updated by the codecoverage plugin to
point to .../.netbenas/6.5/modules/ext/emma.jar, and the tests fail on huston because emma's RT class cannot be found if
this private.properties file is accidentally checked in.