[Inkscape-user] Can I create a color gradient in Inkscape?

I have some PNG files that I want to convert into gradients for gimp. I've read that you can export SVG files from inkscape and gimp will read them. The gradients are way too complicated to use gimp's gradient editor and are color from end to end.

When I try to create a gradient from a PNG file in inkscape and export to SVG, gimp picks up two black fading to transparent gradients. I think I've read all the documentation and have googled this to death over the past couple days.

Can this be done, and if so, can someone please point me toward instructions on how to do it.

TIA,

Jim