How do I add units?

[QuintusSertorius]

I don't know what it is with my game and some of the cheats, but I just get an error every time I try to use create_unit.

For example I put in:

create_unit Sala african skirmisher javelinmen 2 0 0 0

And it just says err: unit not recognised. I've got a long list of ones I'd copied out of the descr_names.txt (which are the same as the type in the EDU) and none of them work. Get the same error every time, it doesn't recognise the names of the units I put in.

I'm trying to boost the Sab'yn garrisons in settlements I gave to them, and also in Spain boost Qarthadastim garrisons so they might try to conquer Spain.

Any ideas?