On my Linux box using an older javaws I can pass a system property to Java via javaws with something like
javaws -J-Dsome.key=some.value http://some.jnlp
However it seems on my Mac using a newer version of javaws this does not work. The "-Dsome.key=some.value" is not passed to the java process (looking at the java process launched by javaws, the -D option is simply not there). However, other Java options are passed without issue, eg.
javaws -J-verbose:gc http://some.jnlp
works fine on both Linux and Mac (I can see the -verbose:gc option fine in the java process launched by javaws).
Does anyone have any ideas? Is it a security setting? Is it a bug in javaws on Mac?