When exporting a mesh as Collada, the exporter should check for the material shadeless flag, and output a constant material instead of a phong if enabled.
The exporter outputs a phong material regardless of the state of the shadeless flag.
I found an old diff addressing this exact issue, but it seems that it was reverted about a month after merging. I still need this feature, are there any plans to address it? I'm ultimately converting my Collada models to glTF though, so if this is addressed in the upcoming glTF exporter that's good enough for me.
Running Blender 2.77a (abf6f08) on Ubuntu Linux 15.10 64-bit.