TYPO3 Core

Thanks to Peter Klein for this interim fix...

Place your own mp3.gif file in typo3/gfx/fileicons/ (see gif file attached to this bugreport)

Add this to your typo3/extTables.php (or ext_tables.php in an extension) to override the mapping in t3lib/stddb/tables.php:

$FILEICONS['mp3'] = 'mp3.gif';

Peter also noted that other media file types are also missing, such as:
MP4, FLV, WMA, WMV

And I noticed that the whole mapping concept is not ideal.

Who needs icons to see which extension a file has? Better would be t use one icon for a type. Possible types are:

text (plain text, ms word, oo writer, etc)
spreadsheets (csv, ms excel, oo calc, etc)
presentations (ms powerpoint, oo impress)
images (gif, png, jpeg, etc)
videos (mpeg4, windows media video, quicktime, etc)
interactive videos (flash, etc)
audio (MP3, windows media audio, ogg vorbis, etc)
etc
etc

fixed in SVN