diff --git a/src/main/org/apache/tools/ant/launch/Locator.java b/src/main/org/apache/tools/ant/launch/Locator.java
index eb3efe995..62a9b7692 100644
--- a/src/main/org/apache/tools/ant/launch/Locator.java
+++ b/src/main/org/apache/tools/ant/launch/Locator.java
@@ -312,8 +312,11 @@ public final class Locator {
                         sb.write((char) ((i1 << NIBBLE) + i2));
                     }
                 }
-            } else {
+            } else if (c >= 0x0000 && c < 0x0080) {
                 sb.write(c);
+            } else { // #50543
+                byte[] bytes = String.valueOf(c).getBytes(URI_ENCODING);
+                sb.write(bytes, 0, bytes.length);
             }
         }
         return sb.toString(URI_ENCODING);
diff --git a/src/tests/junit/org/apache/tools/ant/launch/LocatorTest.java b/src/tests/junit/org/apache/tools/ant/launch/LocatorTest.java
index 8191a061f..51de06139 100644
--- a/src/tests/junit/org/apache/tools/ant/launch/LocatorTest.java
+++ b/src/tests/junit/org/apache/tools/ant/launch/LocatorTest.java
@@ -172,6 +172,10 @@ public class LocatorTest extends TestCase {
         char umlauted = result.charAt(1);
         assertEquals("expected 0xf6 (\u00f6), but got " + Integer.toHexString(umlauted) + " '"
                 + umlauted + "'", 0xf6, umlauted);
+        assertEquals("file:/tmp/a%C3%A7a%C3%AD%20berry", Locator.encodeURI("file:/tmp/a\u00E7a\u00ED berry"));
+        assertEquals("file:/tmp/a\u00E7a\u00ED berry", Locator.decodeUri("file:/tmp/a%C3%A7a%C3%AD%20berry"));
+        assertEquals("file:/tmp/a\u00E7a\u00ED berry", Locator.decodeUri("file:/tmp/a\u00E7a\u00ED%20berry")); // #50543
+        assertEquals("file:/tmp/hezky \u010Desky", Locator.decodeUri("file:/tmp/hezky%20\u010Desky")); // non-ISO-8859-1 variant
     }
 
     public void testOddLowAsciiURI() throws Exception {