diff --git a/WHATSNEW b/WHATSNEW
index d0f41b60d..81842d77c 100644
--- a/WHATSNEW
+++ b/WHATSNEW
@@ -119,7 +119,11 @@ Fixed bugs:
   Bugzilla Report 19187.
 
 * file names that include spaces need to be quoted inside the @argfile
-  argument using forked <javac> and JDK 1.4.  Bugzilla Report 10499.
+  argument using forked <javac> and (all JDKS).  Bugzilla Report 10499.
+  NB : a first correction was only introducing quotes for JDK 1.4
+  It has been changed to quote for all external compilers when paths contain spaces.
+  Also the backslashes need to be converted to forward slashes 
+  Bugzilla Report 17683.
 
 * Setting filesonly to true in <zip> and related tasks would cause the
   archives to be always recreated.  Bugzilla Report 19449.
diff --git a/src/main/org/apache/tools/ant/taskdefs/compilers/DefaultCompilerAdapter.java b/src/main/org/apache/tools/ant/taskdefs/compilers/DefaultCompilerAdapter.java
index b4c2442a3..11032fed8 100644
--- a/src/main/org/apache/tools/ant/taskdefs/compilers/DefaultCompilerAdapter.java
+++ b/src/main/org/apache/tools/ant/taskdefs/compilers/DefaultCompilerAdapter.java
@@ -405,7 +405,7 @@ public abstract class DefaultCompilerAdapter implements CompilerAdapter {
      * system.
      */
     protected int executeExternalCompile(String[] args, int firstFileName) {
-        return executeExternalCompile(args, firstFileName, false);
+        return executeExternalCompile(args, firstFileName, true);
     }
 
     /**
@@ -415,7 +415,7 @@ public abstract class DefaultCompilerAdapter implements CompilerAdapter {
      * if the index is negative, no temporary file will ever be
      * created, but this may hit the command line length limit on your
      * system.
-     * @param quoteFilenames - if set to true, filenames containing
+     * @param quoteFiles - if set to true, filenames containing
      * spaces will be quoted when they appear in the external file.
      * This is necessary when running JDK 1.4's javac and probably
      * others.
@@ -448,6 +448,7 @@ public abstract class DefaultCompilerAdapter implements CompilerAdapter {
                     out = new PrintWriter(new FileWriter(tmpFile));
                     for (int i = firstFileName; i < args.length; i++) {
                         if (quoteFiles && args[i].indexOf(" ") > -1) {
+                            args[i] = args[i].replace('\\', '/');
                             out.println("\"" + args[i] + "\"");
                         } else {
                             out.println(args[i]);
diff --git a/src/main/org/apache/tools/ant/taskdefs/compilers/JavacExternal.java b/src/main/org/apache/tools/ant/taskdefs/compilers/JavacExternal.java
index 7e0cf39d1..2aa27e8ef 100644
--- a/src/main/org/apache/tools/ant/taskdefs/compilers/JavacExternal.java
+++ b/src/main/org/apache/tools/ant/taskdefs/compilers/JavacExternal.java
@@ -80,8 +80,7 @@ public class JavacExternal extends DefaultCompilerAdapter {
 
         return 
             executeExternalCompile(cmd.getCommandline(), firstFileName,
-                                   !assumeJava11() && !assumeJava12() 
-                                   && !assumeJava13()) 
+                                   true)
             == 0;
     }