Importing Soft & Hard edges into Unity
1) open the following file in a text editor: "Applications/Unity/Unity.app/Contents/Tools/FBXMayaExport.mel"
Search for: FBXExportHardEdges Remove the // in the beginning of that line. You need to do that only once and probably do the change again when updating unity.
2) In unity: Open the Import Settings... for the maya file. Uncheck "Automatically Calculate Normals"
After you have done this, normals will be imported just like they are in maya.