After googling a little bit I can find a way to set the tabIndex in my jsp fragments which are embeded in a jsp. I'm working with JSF and project woodstock.
I have embeded the fragment like this:
<div style="border-bottom: solid rgb(5, 5, 158) 1px; top: 1289px; position: absolute">
<jsp:directive.include file="myFragment.jspf"/>
</div>
I'll be really gratefull for your help.