I found a form of the Parameters.Append command which does work. That being:
cmd.Parameters.Append cmd.CreateParameter("i_User_ID", adInteger,
adParamInput, 8, 1)

Why this works and the other does not, beats me.

I am guessing that I only need to use the "Refresh" method if I did not want
to create my parms manually.

So now I get through the code which allows me to add my parameters. My
current problem is my last parameter "type" is an Oracle Ref Cursor. I'm not
sure what type this translates to in ADO terms.... So I guess I will try a
few and see if any work.