[news.eclipse.platform.pde] Headless build contribute root files twice w

[patrick@xxxxxxxxxxxxx (Patrick Roumanoff)]

Hi,

I had a pde headless build for a product with the JRE being contributed 
through a feature and everything was working fine.

Now I want to enable p2 for this build, so I added p2.gathering=true to my 
build.properties and after solving a few issues and defining an update 
site for external dependencies I have a successful product build.

So far so good. But wait, now the zip is 30Mo bigger because the JRE is 
included twice:
- once under the jre folder as it should be
- once under p2/org.eclipse.equinox.p2.core/cache/binary in a single file 
called [feature name]_root.win32.win32.x86_1.0.0

I have tried manually removing the cache folder and the product seems to 
be launching properly, I haven't try the run a p2 update yet.

So my questions are:
1) Is this file necessary?
2) How can I avoid generating this file?

thanks in advance,
Patrick.