However, Open Office cannot create PDF files with attached exotic files like XML and zip files.
Thus I have created a simple, Free Open Source Java application, for creating PDF with attachments. These attachments can be annotated as well.
It is of pre-alpha quality or developmental release for other developers and power users, to experiment.
The distribution can be downloaded from:
http://www.ashishbanerjee.com
The distribution contains source as well as Java binary. Just unzip it into a directory and execute run.bat. For Linux and Solaris, just rename the run.bat to run.sh and give executable permissions. It needs Java runtime.
LePaOf uses third party open source lib. PDF BOX.