I find a way to do this, but I still have a problem : some comments which are near the same position in 2 or more PDF are not displayed nor assembled. To be exact, only one of them are kept in the output file.
Have you any idea how to solve this ?
Thanks for your help !
FYI, this is how i assemble them :
<Comments result="allComments.xfdf" format="XFDF">
<PDF source="doc2" />
<PDF source="doc3" />
</Comments>
<PDF result="output.pdf" save="FastWebView">
<PDF source="doc1" />
<Comments source="allComments.xfdf" />
</PDF>