   That is the problem. That midplane does not support 10Gb. You will have to replace the midplane with the 1.1 version.
Need some help if someone knows how to to setup this switch. I have a M1000E chassis with this Dell Force 10 MXL installed. The 10GBase-T Module is installed. I setup the tengigabitethernet 0/1 to switchport and 10000mbit. All I want is my blades to communicate across the 10gig interface. The blade servers running server 2008 R2 are connecting auto negotiate at 1gb. I set them to 10gig full and now the interface shows the cable is unplugged. Can someone give me some insight on what I am doing wrong?  
Dell Force 10 MXL 10/40GbE switch