How long is pollen good for?

I have about a dozen or more and im growin' from seed so im sure i'll have a few males. I'm gonna want to do some breeding later so how long is pollen good for and what is the best way to store it?

in the open, it's viable for 2-4 weeks. in a jar, at room temp, 3-6 weeks. in a freezer, 6-12 months, with steadily decreasing viability. i have had some pollen take after 3 years in the freezer, but only produced a few seeds from a totally pollinated plant.