Panics and freeze using age0

[Gabriele Cecchetti]

I'm running FreeBSD 7.1-PRERELEASE over Asus P5Q motherboard.
Such board comes with an nic requiring age0 driver.
When the nic is under load, such trasferring big amount of data
over gigabit connection (let's say some gigabyte backups),
the computer hangs, sometimes with panic, sometimes freezing.

Before that i was using an Intel nic with em0 driver
and 7.0-Stable#2.. and that configuration was really stable.

Looking at the backtrace we found that the page fault happened
during pmap operations (sorry I've not the backtrace anymore to attach 
to this mail).
Another problem with age0 driver was that when the machine boot, the nic
goes up and down and then remain down. Everytime, gaining control of it 
was a mess.

Anyone with similar experience ?
age0 driver is well tested for production enviroment or not ?
Is better to buy another Intel card and going on using em0 driver ?
Any other problems affecting this release just now ?

And, last question, 7.1-PRERELEASE should belong to the STABLE tree ?
In that case why during the last two months is so instable for 
production enviroment ?

Maybe I'm wrong, so I accept suggestions.

Cheers
Gabriele