My thought also. The use of women is something new, though. Arabs would not have done it.
I wouldn't put anything past those barbarians. Come to think of it, a burka can hide the sex of its wearer as well as a bomb strapped to the body. If anything good comes out of this recent suicidal act (prayers for the wounded Russian soldiers) it will be that the Marines, allies and anti-Taliban/OBL forces will be on the look out for this sort of stuff.