Dear Alan
Saw today your comments re Jackafrom 2001 et al. I'm not too sure how much space I have here so I'll give you my email address: malrowe41@yahoo.co.uk - please use it to contact me and make the subject matter 'JACKA' so that I don't think it is spam and delete it.
My name is Malcolm Rowe & I live in Perth, Western Australia despite the email address.
My interest is that my mum's name was Irene JACKA and I have a fair amount of interest in and details of troops of Jackas in Oz. You are quite correct about Jago etc but the origins of the name are Britainy, a derivitive of JACQUES, this being a Celtic land and the probable origin of the Cornish, Welsh, some Irish and some Scots as the Celt expanded westwards back in the mists of time.
I'm probably running out of space here but would love to have a look at your info and share mine so please contact me when you can.
Best wishes
Malcolm