Getting email and turning off broadband

[menion]

I just got an Omnia last week and am still trying to figure everything out. For the first few days, I could not figure out why my battery was constantly so low. I'd charge it to 100, and not too much later I'd surf the web some and I'd notice it was at 50% or lower. I think I figured out the problem, I noticed several times that the wireless status had broadband as connected for hours on end. I'd hit disconnect, only to find it reconnected later. I had my email set to check email every 15 minutes. I set that to an hour. Same problem. I'd look at the wireless and notice brodband has been connected for hours. I set it to manually connect and the problem has gone away. So I'm pretty sure thats it.

How can I fix this? I want it to grab my email, but not leave the connection open and drain my battery.