There was a lens supplement in AP a while back that had a couple of handy tips.

One is to create a saturation adjustment layer, select the magenta colour range then using the dropper options select the exact colour of the purple fringing and desaturate using the slider.

Another method suggested is to duplicate the image and blur the duplicate layer by 5 pixels. Change the blend mode of the duplicate to Colour and the original image reappears largely minus the fringing. In the AP article this was mainly aimed at red fringes but I find it also works on purple.

One issue with both methods is that they can adversely affect other parts of the image so what I tend to do is apply a mask and paint on the mask to reveal the adjustment only where it's needed.

Another method I have used is to create a blank layer set to Saturation mode and then paint with black, on this layer, over the fringing which desaturates it. Fine control can be achieved either by painting at less than 100% brush density or by lowering the layer opacity afterwards.

PS

Something on your deviant art link generates an error message in IE7 about a script causing the browser to run slowly and or crash (it crashed). Don't know whether this affects other browsers or just IE7 but might need looking at...