Which version of mono used in Unity 3.2?

Which version of mono used in Unity 3.2?

mono --version says Mono JIT compiler version 2.0 (Visual Studio built mono)

which tells me nothing.

Does Unity 3.2 use mono 2.6 or mono 2.8? Can I use .NET 3.5 target in compilation (which supported by mono 2.6) or .NET 4.0 target (which supported by mono 2.8)?

I think it should be better to show mono version in help/about menu.

Unity 3.2 uses a mono 2.6 (slightly customized with some bug fixes of ours).

Use the following code in a C# script to get the Mono version Unity is currently using:

using UnityEngine;
using System;
using System.Reflection;

var type = Type.GetType("Mono.Runtime");
if (type != null) {
 var dispalayName = type.GetMethod("GetDisplayName", BindingFlags.NonPublic | BindingFlags.Static);
 if (dispalayName != null)
 Debug.Log(dispalayName.Invoke(null, null));

As of Unity 3.5.4 it’s Mono 2.6.5.