Frustum plane undefined

Hi everybody,

When I use 2.5 beta, on some projects I get a frustumPlanes[p] is undefined  error, in this method :

The problem doesn't occur in 2.4 final. I think it first occured from commit 3afb8d05108e032c285136a216bf98cb718419da "Added camera.isInFrustum and camera.isCompletelyInFrustum"

BoundingBox.IsCompletelyInFrustum = function (boundingVectors, frustumPlanes) {
  for (var p = 0; p < 6; p++) {
    for (var i = 0; i < 8; i++) {
      if (frustumPlanes[p].dotCoordinate(boundingVectors[i]) < 0) {
        return false;
      }
    }
  }
  return true;
};

For now I didn't manage to figure out what the difference is between projects where this error occur and those where there is no problem.