Revision 549 adds support to use older versions of the C# compiler with SharpDevelop 2.0.

In the "Compiling" options page of the project, you can set the version you want to use. If you use anything else than "Default (.NET 2.0)", SharpDevelop will modify the project file to use a custom MsBuild target file from the SharpDevelop directory that allows you to specify a different compiler version and reference older versions of mscorlib and the System libraries.

If you want to use MsBuild.exe in the command line to compile your projects, you will now need to specify the directory where SharpDevelop is installed:

"MsBuild /property:SharpDevelopBinPath=C:\Programs\SharpDevelop\2.0\bin"