title: jstack Can't create thread dump - Thread 745: (state = BLOCKED) Error occurred during stack walking)
body: <p>When we generate a thread dump for JBoss 4.2.3.GA using $JAVA_HOME/bin/jstack on Linux... we get this error:</p>
  
  <pre><code>Can't create thread dump - Thread 745: (state = BLOCKED) Error occurred during stack walking) 
  </code></pre>
  
  <p>Any ideas why this might be happening? I thought maybe someone was running a heap dump at the same time. Any other ideas? </p>