This was from daywalker04 of the modmymoto forum.
This seem edit is confirmed to work on both MLD and LD firmwares.
Open the seem 004e_0001.
Change the values at the offsets 920, 921, 922 and 923 to FF. (It does not matter what the values are present currently)
Save the seem and re-start the phone.
Go to media finder, select any music file you want to, go to options and now the "Apply As" menu appears. Select Ringtone
Note that, we cannot select ringtones from the Ring Styles menu. We can do it only from media viewer.
I generally do seem editing using P2kToolsVS. Attached is the screen shot of the seem from my phone.
I wish we had a similar seem edit for e398 as well