ASP.NET C# SAP Crystalreportsviewer theming problem

I've placed a crystalreportsviewer on the page with a hardcoded stylesheet defined and theming disabled. In the following code snippet you see how I've declared the crystalreportsviewer:

<CR:CrystalReportViewer ID="CrystalReportViewer1" runat="server" AutoDataBind="true" HasCrystalLogo="False" BestFitPage="False" Width="100%" PageZoomFactor="75" CssFilename="~/App_Themes/ReporterStyle.css" EnableTheming="false" />

My problem is that the default theming kicks in instead of my own stylesheet / theme.

What have i done:

1. Found the website: http://msdn.microsoft.com/en-us/library/ms225493%28v=VS.90%29.aspx to enable an own stylesheet, which didn't fix my problem.
2. Found another website where they suggest to set the property EnableTheming to false, which didn't fix my problem.
3. I wanted to understand why it didn't load my style. I've used fiddler to discover what happens. It loads my own defined style but surprisingly it loads also a default one.
4. I've also placed a question on the SAP business forums, but I didn't received any reply on it there yet.

Current env开发者_运维知识库ironment:

• ASP.NET 4.0 C#
• Visual Studio 2010 Ultimate
• Crystalreportsviewer 13 (Latest from the SAP website)