Here's sorta kinda a solution.

This is a render with two light sources.  One is just a normal bulb light.  The other is a glowing spher set to a glow value of 2000 using indirect GI.  I rendered this with the setting jacked up for quality so there is a price for using this idea.

1.)  It's limited on how it impacts the scene.  In other words, you don't have a lot of control of things.

2.)  Even with the setting pumped way up, there are still limits to the artifacts that can appear.  You can jack stuff up a lot more than I have here and get the quality even higher but you will pay for it in render time.

Anyway, this is an option that can be used for two light sources which produce two significantly different highlighting results.

Basically, I think you will get better results using the DCG plug-in.  It really depends on how much energy you're willing to pound into an image.

-Kix