ModelImporterTangents editor enumerations: why these what appear in inspector differ from these from docs?

I have just tried to rewrite the modelimport settings script from here:
http://wiki.unity3d.com/index.php/ModelImporterPresetManager

But I am getting errors:
ArgumentException: The requested value ‘CalculateLegacy’ was not found.
System.Enum.Parse (System.Type enumType, System.String value, Boolean ignoreCase) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System/Enum.cs:692)
System.Enum.Parse (System.Type enumType, System.String value) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System/Enum.cs:547)

There seem to be some ModelImporterTangents editor enumerations inconsistencies.
How to fix that?

Well, the modelimporter shows a custom selection which is defined inside the modelimporter itself:

It basically uses two arrays, one with “ModelImporterTangents” values and one with GUIContents which are displayed:

// array with ModelImporterTangents values
0 - ModelImporterTangents.Import
1 - ModelImporterTangents.CalculateMikk
2 - ModelImporterTangents.CalculateLegacy
3 - ModelImporterTangents.CalculateLegacyWithSplitTangents
4 - ModelImporterTangents.None

// array with GUIContent values
0 - TangentSpaceOptionImport               --> "Import"
1 - TangentSpaceOptionCalculate            --> "Calculate Tangent Space"
2 - TangentSpaceOptionCalculateLegacy      --> "Calculate Legacy"
3 - TangentSpaceOptionCalculateLegacySplit --> "Calculate Legacy - Split Tangents"
4 - TangentSpaceOptionNone                 --> "None"

So the association would be

ModelImporterTangents.Import                           --> "Import"
ModelImporterTangents.CalculateMikk                    --> "Calculate Tangent Space"
ModelImporterTangents.CalculateLegacy                  --> "Calculate Legacy"
ModelImporterTangents.CalculateLegacyWithSplitTangents --> "Calculate Legacy - Split Tangents"
ModelImporterTangents.None                             --> "None"