Loading the b43 driver without any options knocks out bluetooth. Pairing fails with a timeout, and there will be dbus entries like this in /var/log/messages:

dbus[1851]: [system] Rejected send message, 0 matched rules; type="method_return", sender=":1.15" (uid=0 pid=2255 comm="/usr/bin/python /usr/bin/blueman-applet ") interface="(unset)" member="(unset)" error name="(unset)" requested_reply="0" destination=":1.1" (uid=0 pid=1875 comm="/usr/sbin/bluetoothd ")


lspci for the wifi controller:
0c:00.0 Network controller: Broadcom Corporation BCM4312 802.11b/g LP-PHY (rev 01)

lsusb for the bluetooth contrller:
Bus 003 Device 005: ID 413c:8160 Dell Computer Corp. Wireless 365 Bluetooth



Fix:
load the b43 driver with the "btcoex=0" option.

The way I did this was to blacklist the b43 driver via a file /etc/modprobe/b43.conf that contained "blacklist b43" on one line. Then went into /etc/rc.d/rc.modules and added a line at the end "/sbin/modprobe b43 -v btcoex=0". There should be a way to do this with udev rules, but I'm not that familiar with udev yet.

Hope this helps anyone with an old inspiron 1545.

The bcm4312 doubled as a combination bluetooth+wifi adapter. To use it effectively you have to use the proprietary driver from Broadcom, the wl (broadcom-sta) driver, rather than the standard kernel b43 driver with the b43 firmware.

Follow the instructions here to use the provided scripts to build and install the driver for your system:

http://slackbuilds.org/repository/14.../broadcom-sta/

Just make sure the Bluetooth daemon is running, and it should work.