Color render bug in scatter?

Hi all,

While playing around with scatter plots, I noticed something strange
about the colors displayed. For example,

f = plt.figure()
ax = f.gca(projection='3d')
ax.scatter([1,2,3], [1,2,3], [1,2,3], 'o', c=[(0,0,1,1), (0,0,0,1), (1,0,0,1)])
plt.show()

should show a blue, a black and a red dot. Instead, my first dot is
grey. It's almost as if the axes "panels" are displayed over it. Is
this a bug, or am I doing something I shouldn't?

Regards
Stéfan