Radio Poppers JRX question

[kami]

I am considering of buying a wireless trigger system to control my 3 SB600's and am leaning toward the RP JRX system. The built in CLS on my Nikon D80 does have it's limitations so I need a more reliable means to control light remotely.

Upon reading on the RP website, it mentions that the system is compatible with flashes that have a sync port.

1. My SB600's do not have sync ports, is there a way around that?

2. Does the RP JRX transmitter have to sit on top of a master flash instead of directly on the camera hotshoe?

I just emailed them so hopefully I get answers. But I hope to hear from those who have actually used them.

Thanks!