Zeilenumbruch / mehrere Zeilen im AlertDialog

StringBuilder sb = new StringBuilder();
sb.append("Hallo");
sb.append(System.getProperty("line.separator"));
sb.append("Das ist ein Test.");

AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage(sb.toString())
         .setPositiveButton(...)
         .setNegativeButton(...)
  	 .setTitle(...)
  	 .setIcon(...);

AlertDialog alert = builder.create();    	        	  	  				
alert.show();

String txt = "zeile1\nzeil2\nzeile3\n...";