Sorry, but I think you're out of luck.
I've just checked the IlohaMail Blog
site, and it would appear that they have ceased development. The last entry on the development blog was on 4/15/05, and the last on the main blog was Wed Jan 25, 2006. The forums just return a blank page.
As regards NTH, I've never heard of it, but if this is who you mean NTH Group
then you may also be out of luck as the latest news was dated 19.3.2009.
Sorry I can't be of any more help, but as you know we do have an extensive membership here and someone might be able to assist.