mono: How to change target framework

How do i change mono to run code made for .NET 4 intead of 2? I'm on Ubuntu Server 11.04

mono --version gives me this:

mono --version
Mono JIT compiler version 2.6.7 (Debian 2.6.7-5ubuntu3)
Copyright (C) 2002-2010 Novell, Inc and Contributors. www.mono-project.com
        TLS:           __thread
        GC:            Included Boehm (with typed GC and Parallel Mark)
        SIGSEGV:       altstack
        Notifications: epoll
        Architecture:  x86
        Disabled:      none

Supposedly i need to run mono 2.8 or greater. So i ran this script (Ubuntu) and rebooted but 开发者_开发问答it still looks like i have the same version.

Edit #1: When i get an error i see this at the bottom:

Version information: Mono Runtime Version: 2.6.7 (Debian 2.6.7-5ubuntu3); ASP.NET Version: 2.0.50727.1433

Edit #2: When i try to install the mono-parallel 2.10 deb package as suggested by skolima's answer and here. I get the following error:

dpkg: error processing mono-2.10.1-parallel-environment.deb (--install): package architecture (amd64) does not match system (i386) Errors were encountered while processing: mono-2.10.1-parallel-environment.deb

But i don't see any alternate downloads for i386.

The script you have used installs additional Mono environment in /opt/mono-2.10 . To use it, you would have to follow instructions from http://www.mono-project.com/Parallel_Mono_Environments . In short:

• create a file ~/mono-2.10-env with the following contents:

#!/bin/bash
MONO_PREFIX=/opt/mono-2.10
GNOME_PREFIX=/usr
export DYLD_LIBRARY_FALLBACK_PATH=$MONO_PREFIX/lib:$DYLD_LIBRARY_FALLBACK_PATH
export LD_LIBRARY_PATH=$MONO_PREFIX/lib:$LD_LIBRARY_PATH
export C_INCLUDE_PATH=$MONO_PREFIX/include:$GNOME_PREFIX/include
export ACLOCAL_PATH=$MONO_PREFIX/share/aclocal
export PKG_CONFIG_PATH=$MONO_PREFIX/lib/pkgconfig:$GNOME_PREFIX/lib/pkgconfig
export PATH=$MONO_PREFIX/bin:$PATH
PS1="[mono2.10] \w @ "

• source it in your shell

source ~/mono-2.10-env

and the current shell session will be running the new Mono. Remember that it is installed outside the normal tree, and apt will not update it. In general, I'd recommend choosing a distro which provides packages that aren't two years old. Also, this is a duplicate of https://askubuntu.com/questions/5304/upgrading-to-latest-stable-mono .