Loosen up bindings??

I recently picked up some new bindings for my board for the new season. Well, not really new (2005 Hyperlite ERA's), but new to my board. The feel really good, and they are definitely the right size, but they are so tight to get on even with lots of binding slime. Plus this weekend, I could barely get them off (I had to use slime for this too.) I'm scared that if they're too tight, and I boarding and wipe-out, the board will not release from my feet when it's supposed to. Does anyone know the best way to stretch them out during the week until they're broken in?

slip some beer bottles or tennis balls, or even something bigger, like an aerosol spray can maybe?, in them after soaking them in some hot water. It should stretch them out a little bit. I did this to my Ultras when I first got them, along with loosening the overlays nearly all the way, and haven't had a problem with them being too tight like everyone else seems to have.