How do I get the editor to work on a page?

In CMS 5 I used this in apsx:
<EPiServer:Property id="myHtmlEditor" Width="650" height="350" EditMode="true" runat="server" />

And this on cs:
override void OnInit(EventArgs e)
{
base.OnInit(e);
if (!Page.ClientScript.IsClientScriptIncludeRegistered("system.js"))
{
Page.ClientScript.RegisterClientScriptInclude("system.js", ((PageBase)Page).ResolveUrlFromUI("javascript/system.js"));
Page.ClientScript.RegisterClientScriptInclude("system.aspx", ((PageBase)Page).ResolveUrlFromUI("javascript/system.aspx"));
Page.ClientScript.RegisterClientScriptInclude("episerverscriptmanager.js", ((PageBase)Page).ResolveUrlFromUtil("javascript/EPiServerScriptManager.js"));
}
PropertyLongString longString = new PropertyLongString();
// select chosen options or use EditorToolOption.All

longString.EditorToolOptions = EditorToolOption.All;
longString.Name = "MyLongStringProperty";
myHtmlEditor.InnerProperty = longString;
}

But when using the exact same code in CMS 6 I only get an empty TextBox with no ToolBox.

Is there any settings needed to be done?