diff --git a/build/classes/xid/Presenter.class b/build/classes/xid/Presenter.class
index f962186..dfcf48f 100644
Binary files a/build/classes/xid/Presenter.class and b/build/classes/xid/Presenter.class differ
diff --git a/dist/xid.jar b/dist/xid.jar
index 10790f7..873386b 100644
Binary files a/dist/xid.jar and b/dist/xid.jar differ
diff --git a/src/xid/Presenter.java b/src/xid/Presenter.java
index e3d965e..b260daf 100644
--- a/src/xid/Presenter.java
+++ b/src/xid/Presenter.java
@@ -13,6 +13,7 @@ import org.w3c.dom.*;
 public class Presenter
 {
   static protected org.apache.log4j.Logger log;
+  static final public char INDEX_SEPARATOR = '_';
 
   static
   { 
@@ -781,7 +782,7 @@ public class Presenter
 	    // Don't forget the list case.
 	    if ((attr.getNodeName ().equals ("id")) && (prefix.length () != 0))
 	      {
-		result.append ('_');
+		result.append (Presenter.INDEX_SEPARATOR);
 		result.append (prefix);
 	      }
 
@@ -1197,7 +1198,7 @@ public class Presenter
 
 	if ((attribute.getKey ().equals ("id")) && (prefix.length () != 0))
 	  {
-	    result.append(" " + attribute.getKey () + "=\"" + attribute.getValue () + '_' + prefix + "\"");
+	    result.append(" " + attribute.getKey () + "=\"" + attribute.getValue () + Presenter.INDEX_SEPARATOR + prefix + "\"");
 	  }
 	else
 	  {