This is an abbreviated version of an e-mail that I also posted to the ndiswrapper mailing list. Compressing the long story, I ran into the same problem using CentOS 5 as I had with Fedora Core 6 and ndiswrapper: my laptop (HP Pavilion zv6000 series with a Broadcom BCM43xx wireless NIC) would lock up or spontaneously reboot after a few hours if I brought up the wireless interface. I also tried using the native bcm43xx driver but the system wouldn't even boot. On a whim, I tried the current "plain vanilla" kernel (2.6.21) from kernel.org. My laptop has been up and stable running the 2.6.21 kernel with the wireless NIC up using ndiswrapper ever since.
Does anyone have any idea why the un-patched kernel from kernel.org works fine with ndiswrapper but both the FC6 and CentOS (RHEL) kernels lock up or spontaneously reboot? I built the 2.6.21 kernel by copying the config file for 2.6.18-8.1.1 from /boot and doing a "make oldconfig". Everything is x86_64.
Cheers, Dave
P.S. Frosting on the cake: the secure digital card reader built into the laptop also works with the 2.6.21 kernel.