I am pleased to inform you that this paper has been published online, and is available at http://stacks.iop.org/1367-2630/13/083031 The article has been written in memoriam of dr. Nicolae Nicorovici Plase read the article. I give here the acknowledgement: Acknowledgement. This paper was written in honor of the Romanian scientist Dr. Nicolae Nicorovici (1944-2010) who was very enthusiastic about the study of cloaking effects with the emerging field of metamaterials. This research was financially supported by the National Authority for Scientific Research (ANCS, UEFISCSU), Romania, through project code PN-II-ID-PCE-2011-3-0608.