Yeah; I believe in GIMP 2.6.8 or 2.6.10, they hosed PSPI and only a few plugins (such as GML Matting and a few Flaming Pear plugins) still work. Been to use a surrogate like Irfanview or XNView to run PS plugins; better preview anyway. If you have Python installed, a better solution is to install Shellout
plugin (thanks to RobA) which will launch your external editor of choice, pass the layer you want to operate the filter on (including transparancies; cool stuff) and return the layer back once done.
