How do I encrypt connectionString in app.settings

[RH+]

I have this now:

    <connectionStrings>
        <add name="DataProject.My.MySettings.CobrosConnectionString"
            connectionString="Data Source=***.**.***.**;Initial Catalog=test;User Id=test2;Password=pass123;"
            providerName="System.Data.SqlClient" />
    </connectionStrings>

I get the setting with:
cn.ConnectionString = My.Settings.CobrosConnectionString

How do I set/get the connection string encrypted instead of plain text?
thanks!