For Unity 3.5 Mac OS X are the System.IO.Ports available?

For Unity 3.5 Mac OS X are the System.IO.Ports available?

This declaration:

using System.IO.Ports;

Returns the following error on Mac OS X in Unity 3.5

Assets/Standard Assets/Scripts/Direct Connection/GuiArduinoSerialScript.cs(6,17): error CS0234: The type or namespace name Ports' does not exist in the namespace System.IO’. Are you missing an assembly reference?

By default, I believe in the Player Settings, the API Compatibility Level is set to the .NET 2.0 Subset, which is the subset that is stripped of certain functionality by Unity to decrease overall build sizes.

Switch the API Compatibility Level from ‘.NET 2.0 Subset’ to ‘.NET 2.0’ and this should resolve your reference issue.