HP EliteBook 8470P: driver for WiFi configured but driver file not copied

Setting: Hardware HP EliteBook 8470P, ROS 0.4.9-dev304 bootcd, Driver CD with uncompressed sp62339 driver from the HP drivers website.

The device is configured as "Broadcom BCM943228HM4L 802.11 a/b/g/n 2x2 WiFi Adapter" by the automatic driver installation with a driver CD inserted but the driver file bcmwl5.sys is not copied into system32\drivers. However, a bcmwlcoi.dll is copied (which also exists in the WinXP subfolder), but it is copied from the Win7 subfolder.

Manually copying the files from the WinXP subfolder into system32\drivers activates the WiFi NIC, but wlanconf -s does not find any wireless network, although many available.