diff --git a/src/main/org/apache/tools/ant/Path.java b/src/main/org/apache/tools/ant/Path.java
index 519194ad8..869d3484b 100644
--- a/src/main/org/apache/tools/ant/Path.java
+++ b/src/main/org/apache/tools/ant/Path.java
@@ -107,11 +107,26 @@ public class Path {
      */
     public void setLocation(String location) {
         if (location != null && location.length() > 0) {
-            definition.addElement(translateFile(location));
+            String element = translateFile(location);
+            if (definition.indexOf(element) == -1) {
+                definition.addElement(element);
+            }
         }
     }
 
 
+    /**
+     * Append the contents of the other Path instance to this.
+     */
+    public void append(Path other) {
+        String[] l = other.list();
+        for (int i=0; i<l.length; i++) {
+            if (definition.indexOf(l[i]) == -1) {
+                definition.addElement(l[i]);
+            }
+        }
+    }
+
     /**
      * Parses a path definition and creates single PathElements.
      * @param path the path definition.
@@ -119,7 +134,10 @@ public class Path {
     public void setPath(String path) {
         final Vector elements = translatePath(path);
         for (int i=0; i < elements.size(); i++) {
-            definition.addElement(elements.elementAt(i));
+            String element = (String) elements.elementAt(i);
+            if (definition.indexOf(element) == -1) {
+                definition.addElement(element);
+            }
         }
     }
 
diff --git a/src/main/org/apache/tools/ant/taskdefs/Java.java b/src/main/org/apache/tools/ant/taskdefs/Java.java
index 5018d0d57..81b97b2c4 100644
--- a/src/main/org/apache/tools/ant/taskdefs/Java.java
+++ b/src/main/org/apache/tools/ant/taskdefs/Java.java
@@ -130,7 +130,7 @@ public class Java extends Exec {
         if (this.classpath == null) {
             this.classpath = s;
         } else {
-            this.classpath.setPath(s.toString());
+            this.classpath.append(s);
         }
     }
     
diff --git a/src/testcases/org/apache/tools/ant/PathTest.java b/src/testcases/org/apache/tools/ant/PathTest.java
index 61b3c8aa2..101bfbd76 100644
--- a/src/testcases/org/apache/tools/ant/PathTest.java
+++ b/src/testcases/org/apache/tools/ant/PathTest.java
@@ -167,6 +167,39 @@ public class PathTest extends TestCase {
         p.setPath("\\d;\\e");
         l = p.list();
         assertEquals("5 after setPath", 5, l.length);
+        p.append(new Path("\\f"));
+        l = p.list();
+        assertEquals("6 after append", 6, l.length);
+    }
+
+    public void testEmpyPath() {
+        Path p = new Path("");
+        String[] l = p.list();
+        assertEquals("0 after construction", 0, l.length);
+        p.setLocation("");
+        l = p.list();
+        assertEquals("0 after setLocation", 0, l.length);
+        p.setPath("");
+        l = p.list();
+        assertEquals("0 after setPath", 0, l.length);
+        p.append(new Path());
+        l = p.list();
+        assertEquals("0 after append", 0, l.length);
+    }
+
+    public void testUnique() {
+        Path p = new Path("/a:/a");
+        String[] l = p.list();
+        assertEquals("1 after construction", 1, l.length);
+        p.setLocation("\\a");
+        l = p.list();
+        assertEquals("1 after setLocation", 1, l.length);
+        p.setPath("\\a;/a");
+        l = p.list();
+        assertEquals("1 after setPath", 1, l.length);
+        p.append(new Path("/a;\\a:\\a"));
+        l = p.list();
+        assertEquals("1 after append", 1, l.length);
     }
 
 }