Resurrecting a dead thread with some info for those who need it.
If you have a ringtone that you want to use as a sound file on a JB'ed phone you can do this: (on a windows machine)
Download a free copy of "Switch Audio File converter" from NCH Software and
Install it.
Download a free copy of "iphonebrowser". I find it one of the easier SSH programs to use.
Open iTunes and view your ringtones.
Select the one you want to use.
Right click and select "show in windows explorer".
Left click and hold, and drag the file to your desktop. It will make a copy.
Right click the file and rename it (just change the extension to ".m4a") at this point.
Right click this file and you will see an option for "convert with Switch Sound File Converter". Select it.
Switch Sound will open up, and the file will be in the window. On the bottom left, switch the "output format" to ".aiff".
to the right of that, check the box that say" output to the same folder as source files".
Click on "Convert".
On your desktop you will now have a ".aiff file" of the sound.
Rename it to "new-mail.caf" (with out the quotes).
Connect phone to computer via USB cable.
Start up iphonebrowser.
Navigate as listed in the posting above this one to the proper directory.
In iphonebrowser, rename "new-mail.caf" to something such as "new-mail old.caf". So you still have it if you want to switch back at a later date.
While showing both iphonebrowser window and the desktop at the same time, drag the new-mail.caf file from the desktop and just drop it anywhere in the iphonebrowser window. It will automatically alphabetize the list and you will see it directly below the file you just named "new-mail old.caf".
You're all done here. There is no need to save anything, it's automatic.
Now, you need to respring your iPhone. If you have "SBSettings" from Cydia, that will make respringing easier. If not, either use whatever you have to respring, or turn your phone completely off and back on (you will see the apple screen during turn on).
That should be it. Send yourself an email to verify.
If you find that the new sound is too loud or too low, you can go back into Switch Sound File Converter, and right click on the file, and select "edit audio in wavepad". on the left pane, under "effects", the first option is "amplify louder or softer". Select that, and using the arrows, either raise or lower the gain. Save the file and you're done. You now need to go back into iphonebrowser and replace the file you put in a few minutes ago with this newer one. You will have to respring again for it to take effect.
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