With mantis issue 0008165 we wanted to add wording in the spec to be compatible
to how we (Softing + .NET proto_ecc branch) implemented the ECC KeyDerivation.

However instead of using the suggested wording something different was done,
that changed the semantics in a subtle way:

"When using UnauthenticatedEncryption with Sign only the SigningKey needs to be computed,
however, the length of the derived key material used to calculate the Salt shall be the same as
the length of the derived key material used with SignAndEncrypt."

So please change that sentence to:

"When using UnauthenticatedEncryption with Sign only the SigningKey needs to be computed,
therefore, the parameter L in step 1 to 3 above shall be DerivedSignatureKeyLength,"