diff --git a/brut.j.util/src/main/java/brut/util/OS.java b/brut.j.util/src/main/java/brut/util/OS.java
index aaa564e3..7c508187 100644
--- a/brut.j.util/src/main/java/brut/util/OS.java
+++ b/brut.j.util/src/main/java/brut/util/OS.java
@@ -19,6 +19,7 @@ package brut.util;
 import brut.common.BrutException;
 import java.io.*;
 import java.util.Arrays;
+import java.util.logging.Logger;
 
 import org.apache.commons.io.IOUtils;
 
@@ -26,6 +27,9 @@ import org.apache.commons.io.IOUtils;
  * @author Ryszard Wiśniewski <brut.alll@gmail.com>
  */
 public class OS {
+
+    private static final Logger LOGGER = Logger.getLogger("");
+
     public static void rmdir(File dir) throws BrutException {
         if (! dir.exists()) {
             return;
@@ -80,21 +84,19 @@ public class OS {
 
     public static void exec(String[] cmd) throws BrutException {
         Process ps = null;
+        int exitValue = -99;
         try {
-            ps = Runtime.getRuntime().exec(cmd);
-
-            new StreamForwarder(ps.getInputStream(), System.err).start();
-            new StreamForwarder(ps.getErrorStream(), System.err).start();
-            if (ps.waitFor() != 0) {
-                throw new BrutException(
-                    "could not exec command: " + Arrays.toString(cmd));
-            }
+            ProcessBuilder builder = new ProcessBuilder(cmd);
+            ps = builder.start();
+            new StreamForwarder(ps.getErrorStream(), "ERROR").start();
+            new StreamForwarder(ps.getInputStream(), "OUTPUT").start();
+            exitValue = ps.waitFor();
+            if (exitValue != 0)
+                throw new BrutException("could not exec (exit code = " + exitValue + "): " + Arrays.toString(cmd));
         } catch (IOException ex) {
-            throw new BrutException(
-                "could not exec command: " + Arrays.toString(cmd), ex);
+            throw new BrutException("could not exec: " + Arrays.toString(cmd), ex);
         } catch (InterruptedException ex) {
-            throw new BrutException(
-                "could not exec command: " + Arrays.toString(cmd), ex);
+            throw new BrutException("could not exec : " + Arrays.toString(cmd), ex);
         }
     }
 
@@ -115,30 +117,29 @@ public class OS {
 
     static class StreamForwarder extends Thread {
 
-        public StreamForwarder(InputStream in, OutputStream out) {
-            mIn = in;
-            mOut = out;
+        StreamForwarder(InputStream is, String type) {
+            mIn = is;
+            mType = type;
         }
 
         @Override
         public void run() {
             try {
-                BufferedReader in = new BufferedReader(
-                    new InputStreamReader(mIn));
-                BufferedWriter out = new BufferedWriter(
-                    new OutputStreamWriter(mOut));
+                BufferedReader br = new BufferedReader(new InputStreamReader(mIn));
                 String line;
-                while ((line = in.readLine()) != null) {
-                    out.write(line);
-                    out.newLine();
+                while ((line = br.readLine()) != null) {
+                    if (mType.equals("OUTPUT")) {
+                        LOGGER.info(line);
+                    } else {
+                        LOGGER.warning(line);
+                    }
                 }
-                out.flush();
             } catch (IOException ex) {
                 ex.printStackTrace();
             }
         }
 
         private final InputStream mIn;
-        private final OutputStream mOut;
+        private final String mType;
     }
 }