SMO not available in .NET 4.0? Or is there an easier way to backup a database from code

We upgraded our application to .NET 4.0 a while ago, and now need to add the ability to backup SQL Server 2008 databases from the app. However, it doesn't seem that SMO is available for .NET 4. Is there a workaround or better way to perform a database backup (note that our backups need to be user initiated over a website, so we cannot schedule them).