I am unable to make the auto-eject to work between machines.

I have a simple machine setup: enrichment chamber -> smelter -> chest. Nothing in the back, power is supplied by the bottom.
I am able to auto-eject items from the smeter to the chest, but not from the enrichment chamber to the smelter.

My machine configuration is the same for both machines: dark blue is outputed to the right, auto-eject is on.

More information: using Mekanism-6.0.5.46, with Minecraft 1.6.4.

Thanks @dschub for the help!

You need to make the smelter accept input from the left (i.e. on the right panel, set the left slot to dark red)