exporting DXT3 ...

I'm trying to export a masked grass texture as DDS DXT3 or DXT5. Unfortunately, it seems I cannot use the an additional Alpha Channel (the PS dds export plugin says "too many channels"), so I have to use "unpainted areas" of the rgb channel as transparent parts. When I load the textures with the mask flag, the outlines are faded to white. I would rather like to define a color. I tried the plugins settings:

Fading MIP Maps...>Fade Color

but this didn't seem to fix the problem, but simply colored the entire mesh kind of. I also tried

Image Options > Border color (1 texel)
without success

Is there a way to make the contours fade to a color other than white? Any ideas?

EDIT: c'mon, can't be impossible?

I also had this problem with photoshop... Frustrated the hell out of me, so i gave up :o(

Ok, found something that is partially working...If you don't mind to reduce your colors to 256: save for web as GIF, using Matte color and transparency. Then reimport and export as dds dxt5. Works. Also tried the same with 24bit PNG, no luck, for no obvious reason imho. Will try again...

A way that typically works:

1: Copy the layer
2: Place the copy below the original layer
3: Blur the copy with gaussian blur (with a high value)
4: Set the layer transparency to 0% or 1%
5: Export in the format you need

Don't know if it works for DXT3 but it works for anything else that has edge bleeding problems.

Wow it really works!!! Thanks a lot fredborg!

Suggestion: increase the saturation of the copy, at least for my grass texture this looks better.

Cool tips dudes! Thanks,

IPete2.