diff -r 32e309883246 -r 4cdaaf4c5dca src/share/classes/com/sun/tools/javac/util/AbstractDiagnosticFormatter.java
--- a/src/share/classes/com/sun/tools/javac/util/AbstractDiagnosticFormatter.java	Fri Nov 07 11:45:49 2008 -0800
+++ b/src/share/classes/com/sun/tools/javac/util/AbstractDiagnosticFormatter.java	Wed Nov 12 14:17:03 2008 +0000
@@ -27,13 +27,13 @@
 import java.util.Collection;
 import java.util.Locale;
 import javax.tools.JavaFileObject;
-import java.util.ResourceBundle;
 
 import com.sun.tools.javac.api.DiagnosticFormatter;
 import com.sun.tools.javac.api.Formattable;
 import com.sun.tools.javac.api.DiagnosticFormatter.PositionKind;
 import com.sun.tools.javac.file.JavacFileManager;
 import static com.sun.tools.javac.util.JCDiagnostic.DiagnosticType.*;
+import static com.sun.tools.javac.util.LayoutCharacters.*;
 
 /**
  * This abstract class provides a basic implementation of the functionalities that should be provided
@@ -72,8 +72,13 @@
 
     public String formatMessage(JCDiagnostic d, Locale l) {
         //this code should rely on the locale settings but it's not! See RFE 6443132
+        StringBuilder buf = new StringBuilder();
         Collection<String> args = formatArguments(d, l);
-        return localize(l, d.getCode(), args.toArray());
+        buf.append(localize(l, d.getCode(), args.toArray()));
+        if (d.isMultiline()) {
+            buf.append(formatSubdiagnostics(d, l));
+        }
+        return buf.toString();
     }
 
     public String formatKind(JCDiagnostic d, Locale l) {
@@ -165,6 +170,23 @@
         return sbuf.toString();
     }
 
+    /**
+     * Format all the subdiagnostics attached to a given diagnostic
+     *
+     * @param d diagnostic whose subdiagnostics are to be formatted
+     * @param l locale object to be used for i18n
+     * @return string representation of the subdiagnostics
+     */
+    protected String formatSubdiagnostics(JCDiagnostic d, Locale l) {
+        StringBuilder buf = new StringBuilder();
+        for (JCDiagnostic d2 : d.getSubdiagnostics()) {
+            buf.append('\n');
+            String subdiagMsg = format(d2, l);
+            buf.append(indent(subdiagMsg, DiagInc));
+        }
+        return buf.toString();
+    }
+
     /** Format the faulty source code line and point to the error.
      *  @param d The diagnostic for which the error line should be printed
      */
@@ -201,4 +223,44 @@
     public boolean displaySource(JCDiagnostic d) {
         return showSource && d.getType() != FRAGMENT;
     }
+
+    /**
+     * Creates a string with a given amount of empty spaces. Useful for
+     * indenting the text of a diagnostic message.
+     *
+     * @param nSpaces the amount of spaces to be added to the result string
+     * @return the indentation string
+     */
+    protected String indentString(int nSpaces) {
+        String spaces = "                        ";
+        if (nSpaces <= spaces.length())
+            return spaces.substring(0, nSpaces);
+        else {
+            StringBuilder buf = new StringBuilder();
+            for (int i = 0 ; i < nSpaces ; i++)
+                buf.append(" ");
+            return buf.toString();
+        }
+    }
+
+    /**
+     * Indent a string by prepending a given amount of empty spaces to each line
+     * of the string
+     *
+     * @param s the string to be indented
+     * @param nSpaces the amount of spaces that should be prepended to each line
+     * of the string
+     * @return an indented string
+     */
+    protected String indent(String s, int nSpaces) {
+        String indent = indentString(nSpaces);
+        StringBuilder buf = new StringBuilder();
+        String nl = "";
+        for (String line : s.split("\n")) {
+            buf.append(nl);
+            buf.append(indent + line);
+            nl = "\n";
+        }
+        return buf.toString();
+    }
 }