FileVault 2 / Bluetooth connection / WLAN - OS X Lion 10.7.4

Hi Community.

I have some strange issues concerning the Bluetooth connection of my keyboard and my mouse ever since I enabled FileVault 2 on my iMac (mid-2011 model).

Before enabling FileVault 2, whenever I started my iMac, the keyboard and mouse would simply connect upon booting. Thus when I was asked to enter my password on start-up, I could simply use my keyboard and mouse.

Ever since enabling FileVault 2, when the password prompt shows up, my keyboard and mouse are not connected. I have to press a mouse button and a button on the keyboard, only then they are recognized and the Bluetooth connection is established.

Furthermore, after the system has booted up, during the first minute of use, I regularly suffer Bluetooth connection drop-outs of either the mouse or the keyboard, never both at the same time. Usually it takes a few seconds for the mouse / keyboard to reconnect. Then the connection is stable and I can work as long as I want to without any further drop-outs.

I know this is only a minor problem, but it drives me crazy. Especially, since the connection issues disappear, whenever I disable FileVault 2.

Is there any way to solve this?
I think it must have something to do with the fact that the prompt after enabling FileVault 2 appears at a different point in the boot-up process than without FileVault 2.

Something else happens, whenever FileVault 2 is enabled: after boot-up my iMac connects to my WLAN (Time Capsule 2 GB, 2011 model) and the connection is dead stable. I have Time Machine create backups via WLAN and it works as a charm.
Once the computer goes into sleep mode, upon re-awaking it connects to the WLAN and again the connection is dead stable - until Time Machine kicks in for the hourly update. Then the WLAN is still shown as connected, but the connection is lost, I cannot access the Internet and Time Machine doesn't work anymore.
Until I restart, then things are back to normal.

The problem disappears upon disabling FileVault 2.

And a third issue occurs after enabling FileVault 2: every once in a while, after I entered my password, instead of simply booting up, a status bar appears on the screen. The status is progressing, it appears as if it is loading something or finishing some process. Then the computer boots up, but is incredibly slow.
I have to restart it, to fix the problem.

Again, after disabling FileVault 2, the problem is gone.

I have already run the iMac hardware test, it doesn't show anything out of the ordinary. Most of the time, the system is completely fine and stable.

The problems only occur, when FileVault 2 is active.

Sorry for the lengthy post, but these things really bother me.
I hope they are gone, once Mountain Lion is released.

Are there any solutions?

Regards

Sebastian