The commit message lists all new commits to ET repositories in each build, so I think those are indeed the only changes to the ET code between revisions. The error is most likely unrelated to the changes in the commits. The last successful build (#322) was done on the CCT build slave, as were all of the previous successful builds I checked. The two most recent builds, however, were done on the Caltech slave (since the CCT machine is temporarily offline) and both of those failed. So I guess there must be some problem with the Caltech build slave.