Deploying Content Type with Publishing HTML Field by Feature saving content not correctly

I have a problem using a Publishing HTML Field.

The Elements.xml:

<?xml version="1.0" encoding="utf-8"?>
 <Elements xmlns="http://schemas.microsoft.com/sharepoint/">
   <Field ID="{987B9BA2-23AB-4E52-99DD-2D59BAA79F4B}" Name="LeftContent" DisplayName="Left Content" RichText="TRUE" RichTextMode="FullHtml" Type="HTML" Hidden="FALSE"></Field>
 
 <!-- Parent ContentType: Article Page (0x010100C568DB52D9D0A14D9B2FDCC96666E9F2007948130EC3DB064584E219954237AF3900242457EFB8B24247815D688C526CD44D) -->
   <ContentType ID="0x010100C568DB52D9D0A14D9B2FDCC96666E9F2007948130EC3DB064584E219954237AF3900242457EFB8B24247815D688C526CD44D002da882f450a44abaacff86118ffffaeb"
                Name="Left Content"
                Version="0">
     <FieldRefs>
       <FieldRef ID="{987B9BA2-23AB-4E52-99DD-2D59BAA79F4B}"/>
     </FieldRefs>
   </ContentType>
 
 </Elements>
 

In my Page Layout I use ...

<PublishingWebControls:RichHtmlField id="rchHtmlFldROSTableTwoColumnRight" FieldName="ROSTableTwoColumnRight" runat="server"/>
 

The problem is that when I create a page based on the page layout with this content type and edit the field, SharePoint saves the content not as HTML but HTML Entities. So in not-edit-mode you see the HTML source code like

Hello World

I hope somebody can help me.
Thanks!! ;)

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