Same issue here for a Mac mini (Mid 2010) / Macmini4,1 / MM41.0042.B03 (EFI 1.5)
2,4 GHz Intel Core 2 Duo
OS X: version 10.11.5 (build: 15F34)
Docker.app: version v1.11.1-beta12
vmware fusion is running on same machine, so virtualisation is possible?
The same version docker beta app runs fine on my macbook air: 2 GHz Intel Core i7.
Found this: Fatal Error Incompatible CPU detected
"sysctl kern.hv_support" is 1 on my macbook air and 0 on the mac mini, guess it will not work when it is 0.