diff --git a/src/main/org/apache/tools/ant/util/optional/JavaxScriptRunner.java b/src/main/org/apache/tools/ant/util/optional/JavaxScriptRunner.java
index 3e2ecbd07..0bd3776e4 100644
--- a/src/main/org/apache/tools/ant/util/optional/JavaxScriptRunner.java
+++ b/src/main/org/apache/tools/ant/util/optional/JavaxScriptRunner.java
@@ -95,7 +95,11 @@ public class JavaxScriptRunner extends ScriptRunnerBase {
             }
             // execute the script
             return engine.invoke("eval", String.class, getScript());
+        } catch (BuildException be) {
+            //catch and rethrow build exceptions
+            throw be;
         } catch (Exception be) {
+            //any other exception? Get its cause
             Throwable t = be;
             Throwable te = (Throwable) ReflectUtil.invoke(be, "getCause");
             if (te != null) {