Does freezing butter or margarine change the properties? I have a lot of butter &amp; margarine and looking for ways to keep it for longer time.

Will freezing them change melting point, flavor, or anything that could be undesirable when cooking? 

Update:
We are now freezing our butter and margarine. It is a perfect solution!
Butter and margarine freeze perfectly.  I generally stock up during sales and thaw it as needed. You just have to make sure it's wrapped tightly in the foil, to prevent oxidation.  It'll keep at least 6 months, probably more if you don't have a self-defrosting freezer.

Thawing butter does take quite a while, however.  I usually give a package a few days to thaw fully. If you need butter in a hurry, you can always put it in a Ziploc bag and fast thaw it a bowl under running running water.  Or, just soften it in the microwave.