you need get 2 submodule.
1 git://github.com/masakih/HMXSPFcomponent.git into extFiles/HMXSPFcomponent
2 git://github.com/masakih/HMExtensions.git into extFiles/HMXSPFcomponent/extFiles/HMExtensions

this project contain UKKQueue.
Thanks to M. Uli Kusterer.

