An attempt to open a SourceDataLine leads to LineUnavailableException on Windows 2003 (first catch - JDK7 b32).
See the example below.

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package testapp.sound;

import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.SourceDataLine;

public class LUE {
    
    /** Creates a new instance of LUE */
    public static void main(String[] argv) {
        LUE inst = new LUE();
        
        try {
            inst.m1();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    
    public void m1() throws Exception {
        // Retrieving a line for "any audio format"
        SourceDataLine line = AudioSystem.getSourceDataLine(null);
        System.out.println("Line: " + line.getLineInfo() );
        System.out.println("Java class of the line: " + line.getClass().getName());
        line.open();
    }
}
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The output:
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$ java -cp classes/ testapp/sound/LUE
Line: interface SourceDataLine supporting 8 audio formats, and buffers of at least 32 bytes
Java class of the line: com.sun.media.sound.DirectAudioDevice$DirectSDL
javax.sound.sampled.LineUnavailableException: line with format PCM_SIGNED 44100.0 Hz, 16 bit, stereo, 4 bytes/frame, little-endian not supported.
        at com.sun.media.sound.DirectAudioDevice$DirectDL.implOpen(DirectAudioDevice.java:511)
        at com.sun.media.sound.AbstractDataLine.open(AbstractDataLine.java:124)
        at com.sun.media.sound.AbstractDataLine.open(AbstractDataLine.java:416)
        at testapp.sound.LUE.m1(LUE.java:32)
        at testapp.sound.LUE.main(LUE.java:22)
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