Contenttype feature throws exeception

Today I saw a strange error when creating a feature with a custom contenttype, I had no special field type pretty basic stuff but when the feature was activated this exception was thrown:
Value does not fall within the expected range.   at Microsoft.SharePoint.SPContentTypeId..ctor(String id)    at Microsoft.SharePoint.SPContentTypeElement.ElementActivated(SPFeaturePropertyCollection props, SPSqlCommand sqlcmdAppendOnly, SPWebApplication webApp, SPSite site, SPWeb webNull, Boolean fForce)    at Microsoft.SharePoint.Administration.SPElementDefinitionCollection.ProvisionFieldsAndContentTypes(SPFeaturePropertyCollection props, SPSite site, SPWeb web, Boolean fForce)    at Microsoft.SharePoint.Administration.SPElementDefinitionCollection.ProvisionElements(SPFeaturePropertyCollection props, SPWebApplication webapp, SPSite site, SPWeb web, Boolean fForce)    at Microsoft.SharePoint.SPFeature.ProvisionElements(SPFeaturePropertyCollection props, SPWebApplication webapp, SPSite site, SPWeb web, Boolean fForce)    at Microsoft.SharePoint.SPFeature.Activate(SPSite siteParent, SPWeb webParent, SPFeaturePropertyCollection props, Boolean fForce)    at Microsoft.SharePoint.SPFeatureCollection.AddInternal(Guid featureId, SPFeaturePropertyCollection properties, Boolean force, Boolean fMarkOnly)    at Microsoft.SharePoint.SPFeatureCollection.Add(Guid featureId)    at Microsoft.SharePoint.WebControls.FeatureActivator.BtnActivateFeature_Click(Object objSender, EventArgs evtargs)    at System.Web.UI.WebControls.Button.OnClick(EventArgs e)    at System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument)    at System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument)    at System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument)    at System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData)    at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

First I thought it was some sort of error due to the fact that im inheriting from the picture contenttype, the ULS  and eventlog did not help much.

The contentype element:

After some investigation I realised that the problem was with the ID attribute, don't use capital X in the ID attributes value like above use this instead: