This is really sweet if you get it to work and it shouldn't be too hard.

What you need:

-Ubuntu (I did it in Breezy, may work in other releases)
-XMMS installed
-A Bluetooth dongle or whatever kind of built-in Bluetooth support
-A Symbian powered mobile phone, like Nokia series 60 (7650/3650) or Siemens P800/P900

(If you have a different type of mobile phone, you may be have a look here and see if it is supported by some other software.)

Now, open a terminal and do this:

Code:
sudo apt-get install gnome-bluetooth
sudo apt-get install libgtk1.2-dev
sudo apt-get install xmms-dev
sudo apt-get install libbluetooth1-dev
Visit this site and download the file for your type of phone, then extract the file bemused.sis from the archive. You can delete the archive file now because it contains the ******* version of the server and we don't want that.

Now you need to send bemused.sis to your phone. Enable Bluetooth in your phone's settings. In the terminal, enter:

Code:
hcitool scan
After a while, the name of your phone should appear. Now switch to the directory that contains bemused.sis and enter:

Code:
gnome-obex-send bemused.sis
A dialog box will appear in Gnome. Select your phone and press okay. You should receive the file now and install it on the mobile phone.

(Optional: Install this and include "gnome-obex-send" into your nautilus right-click menu for convenient future use if you want to.)

Now, download "Source code for the Bemused Linux server" from here and extract it. In the terminal window, switch to the directory that you just extracted and do this:

Code:
sdptool add --channel=9 SP
sudo make install
If it doesn't work, post here. If it does, do:

Code:
sudo gedit /etc/bemused.conf
Change the line containing "channel" to:

Code:
channel=9
(Remove the leading "#")

Change the line containing mp3dir so it points to your mp3 directory. Change some more settings if you know what you're doing. Save and quit.

Make sure that XMMS is NOT running. In the terminal, type:

Code:
bemusedlinuxserver -d
XMMS should start. Run the Bemused software on your phone and enjoy.

If you want, you can go to Applications->System Tools->Applications Menu Editor and create a new entry for bemusedlinuxserver.

Have fun!