Printer Marks set as black

Hello

I'm trying to sort out an issue with the printer marks beeing set as black (K) in the print separations dialog.

What I'm trying to do is to print separations to pdf to send out to be printed in plates, for this to work I have to set the option "print separations in color" to true, so that the screen angle does not get screwed when the plates are printed. Now my issue here is that all works well just the printermarks are not iin the color respective to their plate, they all are black. This will result in the plates other than the black one to not have any printermarks.

Now if there is a way to say set them to registration color or something so they are then printed right it would be great, otherwise I would need to se printermarks by hand which is a bit of a pain.

Thanks in advance for any enlightenment.

MFG

Ketraar