Hard to read what that means in practice. What I recollect is that in the British type systems a President is ceremonial and a Prime Minister is the power wielder.
from the link: On Thursday, ministers finally took up their positions, 20 each from Kibaki's and Odinga's camps. Kibaki's party retained the key finance and internal security ministries and Raila's allies will head up agriculture and oversee local government.
The entire government, including Odinga, swore an oath of loyalty to the president...