[Icecast] Modify MP3 Files From Shell

[Andy Woolley]

Hi All,

Sorry about the off topic post but I'm having trouble finding anything that 
will work, thought one of you guys might have a quick answer to my question.

Anyway, I'm looking for a tool that will add fade in and fade out to a .mp3 
file. The problem is that this needs to be a Linux command line utility 
either Open Source or propriatry. I'd like to add a nice fade in and fade 
out to some 30 second sound snippets, anybody?

Your help will be most appreciated.

Thanks very much,
Andy