mime type and html5 audio

[Alice Wonder]

Linux - CentOS 7 to be specific, but my own build of gstreamer replacing 
stock - version 1.6.2 is what I am currently running (I update few times 
every year)

mp3 via html5 in FireFox works when I have the libmad plugin so I know 
firefox is handing that off to gstreamer, but it stopped working with 
tumblr.

When I looked at what Tumblr is doing, they are using "audio/mp3" as the 
type attribute on the audio source node, which is incorrect.

However FireFox on Windows seems to not care, so I think the issue is 
that FireFox on Linux is asking GStreamer if it can handle "audio/mp3" 
and is being told no.

Is there a way within gstreamer to make "audio/mp3" be an alias for 
"audio/mpeg;codecs=mp3" (or just "audio/mpeg") to solve this issue?

Obviously Tumblr should fix their broken code but I have never, not 
once, gotten any kind of response from them on any bugs I reported. They 
seem to develop within their own closed world.

I'm guessing this would require a patch to GStreamer itself, hence why 
this list.

Thanks,

Alice Wonder