Where winamp takes song's title when playing from url

[1rsv]

I've made php script whitch is allow client to play songs from my server. There are links no playlists in m3u format.
Here is example of playlist witch is sent to winamp when client click on link on web page:

#EXTM3U
#EXTINF:546,cool song.mp3
http://my.super.mega.server/playsong.php?song_id=2434
#EXTINF:232,song2.mp3
http://my.super.mega.server/playsong.php?song_id=1232
#EXTINF:134,Al Green - Let's Stay Together.mp3
http://my.super.mega.server/playsong.php?song_id=1647
#EXTINF:245,song5.mp3
http://my.super.mega.server/playsong.php?song_id=1747

When winamp loads this playlist from server it takes titles from it for all songs except current plaing. Title of current playing song it shows as
playsong.php?song_id=blabla

The question is, how can I force winamp to show song's title?

Maybe with http ansver on link playsong.php?song_id=blabla I should send some http headers with song title?

[1rsv]

I've found that I can send in http header this line and winamp uses info from it to display title of current playing song in playlist

"icy-name: here is my song's title"