Error message: Unable to cast object of type 'System.String' to type 'Bone.MultilingualString'.

Url: http://aequip.gr/skin.aspx?lang=el&itemtype=ProductCategory&itemid=00990CA7&action=view&00002328=055D4A8D‡055D4A89‡055D4B0F‡055D4AAA&0098E88A=0098E8F6&009936AC=009936E4&pagesize=48&sortby=priceasc&splitter_products_offset=0

Message: Unable to cast object of type 'System.String' to type 'Bone.MultilingualString'.

   at Bone.Base.get_Meta() in C:\Bone\Bone\src\Classes\Base.cs:line 231
   at Bone.Base.get_Head() in C:\Bone\Bone\src\Classes\Base.cs:line 490
   at ASP.skin_aspx.__Render__control1(HtmlTextWriter __w, Control parameterContainer) in c:\inetpub\wwwroot\skin.aspx:line 42
   at System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children)
   at System.Web.UI.Page.Render(HtmlTextWriter writer)
   at Bone.Asp.RenderSkin(TextWriter w) in C:\Bone\Bone\src\Classes\Asp.cs:line 71
   at Bone.ModalAction.RenderPage(TextWriter w) in C:\Bone\Bone\src\Actions\Modal.cs:line 81
   at Bone.Asp.Render(HtmlTextWriter w) in C:\Bone\Bone\src\Classes\Asp.cs:line 82
   at System.Web.UI.Control.RenderControlInternal(HtmlTextWriter writer, ControlAdapter adapter)
   at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)