properties from extension jnlp are not set

Assume a project with two jnlp files a.jnlp and b.jnlp, where a.jnlp loads b.jnlp as extension.

Both a.jnlp and b.jnlp define a property within the resources.

At runtime, only the property defined by a.jnlp is set, the property defined by b.jnlp is ignored.

With Oracle's webstart, the property is set, even if defined in b.jnlp.