Oh oh sounds like rust! Others here will know what to do. But I would isolate that one plant from all the others until then.

Yup, rust. It can be hard to control.

You cannot eliminate the rust that has already formed, but you can apply a fungicide to help keep it from spreading.

I am currently using a systemic fungicide that I got from my local garden center that you mix and spray in a pump-up sprayer. I am not sure if it is helping or not but at least it is not hurting. I think granules might possibly work better if you can find such a product. I am not clear on the benefits of spraying a systemic product. One would think most of the uptake would be via the root system and not foliage. I am using the same fungicide on my Singapore Obtusa which seems to flirt with black spot and black tip on occasion.

Also, most recommend removing any already infested leaves... put them in a bag and toss them.

The good thing is that I haven't heard of it killing a plant. However, a bad case can strip all the leaves.

it is a fact of life here. It doesn`t effect blooming that I have noticed. Spreads to so many different plants.
Tally HO!