Excellent , the include self was the issue. I had omitted the flag entirely because i did not know the wiki, and was working by modification of the roman general...
I think the wiki will be a huge help. thanks a lot for the fast answer and sorry for the finally so simple question.
Btw, in any engine, is there a way to share the attack boost between unit. I mean, if i design an attack boost and give him a name and make it only based on multiplier, can i reuse it on several units without having to enter the full xml definition in each unit?