App needs to exec script

I need for an app to exec a script. The script I'm testing with is simply mkdir /sdcard/test.dir, and works when directly called. The code compiles and executes, but the script isn't being run. My coding environment is Ubuntu 10.04, Sun JDK 6, Android & vi. No Eclipse.

Thanks in advance. This supposedly simple function has me stumped.

Code :

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public void execCommandLine1()
 
    {
        try
         {
            Runtime rt = Runtime.getRuntime();
            Process proc = rt.exec("/system/xbin/test.sh");
            InputStream is = proc.getInputStream();
            InputStreamReader isr = new InputStreamReader(is);
            BufferedReader br = new BufferedReader(isr);
            String line;
            prompt.setText("default pressed");
 
       while ((line = br.readLine()) != null) {
         System.out.println(line);
       }
           } catch (Throwable t)
          {
            t.printStackTrace();
          }
 
}

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