FULL PRODUCT VERSION :
java version "1.6.0-beta2"
Java(TM) SE Runtime Environment (build 1.6.0-beta2-b86)
Java HotSpot(TM) Client VM (build 1.6.0-beta2-b86, mixed mode, sharing)

FULL OS VERSION :
Linux  2.6.15-26-386 #1 PREEMPT Thu Aug 3 02:52:00 UTC 2006 i686 GNU/Linux

A DESCRIPTION OF THE PROBLEM :
see steps to reproduce and java code

THE PROBLEM WAS REPRODUCIBLE WITH -Xint FLAG: Yes

THE PROBLEM WAS REPRODUCIBLE WITH -server FLAG: Yes

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
create Font instance with "" as font name new Font("", Font.PLAIN, 10) and display a label using this font

EXPECTED VERSUS ACTUAL BEHAVIOR :
Expected: default font to be used
Actual result: crash of JVM
ERROR MESSAGES/STACK TRACES THAT OCCUR :
#
# An unexpected error has been detected by Java Runtime Environment:
#
#  SIGSEGV (0xb) at pc=0xb53bd511, pid=6163, tid=3085335472
#
# Java VM: Java HotSpot(TM) Client VM (1.6.0-beta2-b86 mixed mode, sharing)
# Problematic frame:
# C  [libfontmanager.so+0x2e511]
#
# If you would like to submit a bug report, please visit:
#   http://java.sun.com/webapps/bugreport/crash.jsp
#


REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.awt.Container;
import java.awt.Font;
import javax.swing.JFrame;
import javax.swing.JLabel;

/**
 *
 * @author Igor Minar
 */
public class FontBug {
    
    public static void main(String[] args) {
        JFrame frame = new JFrame();
        Container container = frame.getContentPane();
        
        JLabel label = new JLabel("test");
        label.setFont(new Font("", Font.PLAIN, 10));
        container.add(label);
        
        frame.pack();
        frame.setVisible(true);
    }
    
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
don't use "" as font name, use null instead