After a bit of fiddling with masked ebuilds, I finally managed to get Bluetooth working with Gnome on my AMD64-based Gentoo system. In case you’re running into similar AMD64-related issues, please check out the following bugs I submitted to the Gentoo bug tracker:
The following bug is also relevant:
The HOWTO mobile phone, Bluetooth and GNOME Wiki page is also helpful. Note however that this is somewhat outdated. For example, the bluez-sdp package is deprecated and should no longer be used, as its functionality has been rolled into the other bluez packages.
After setting everything up, I was able to connect to my new Motorola V551 phone and transfer several files and J2ME applications from Gnome / Nautilus.
Leave a comment if you need further help.