port scanning activity going up recently?

Hi all -

	Has anyone else noticed a recent spike in port scan activity over the last
few days?

	I've been seeing some interesting traffic where multiple source addresses
are probing a number of the same high order destination ports from a small
set of source ports with a number of different but specific packet sizes.

	e.g.: source port 3268 -> dest port 50572 packet size 48, 60, 64, and 52
	egg: source port 3268 -> dest port 50592 packet size 48, 60, 64, and 52

	Is there some botnet out there that I haven't heard about?

thanks -- ken