Utilisation de exttld

Bonjour,
J'essaie désespérement de faire fonctionner exttld, mais j'ai des messages d'erreurs.
J'ai par exemple juste voulu utiliser la webapp d'exemple qui se trouve à l'adresse suivante : http://code.google.com/p/exttld/downloads/list, mais j'ai le message d'erreur suivant :

Citation:

Compilation of JSP File '/index.jsp' failed:

tree.treePanel.tag:1412:51: This attribute is not recognized.
<c:if test="<%= BeanUtils.getProperty(this,"loader")!=null %>">
^----^
tree.treePanel.tag:1412:61: This attribute is not recognized.
<c:if test="<%= BeanUtils.getProperty(this,"loader")!=null %>">
^--^
tree.treePanel.tag:1423:50: This attribute is not recognized.
<c:if test="<%= BeanUtils.getProperty(this,"items")!=null %>">
^---^
tree.treePanel.tag:1423:59: This attribute is not recognized.
<c:if test="<%= BeanUtils.getProperty(this,"items")!=null %>">
^--^
tree.treePanel.tag:1430:51: This attribute is not recognized.
<c:if test="<%= BeanUtils.getProperty(this,"tbar")!=null %>">
^--^
tree.treePanel.tag:1430:59: This attribute is not recognized.
<c:if test="<%= BeanUtils.getProperty(this,"tbar")!=null %>">
^--^
tree.treePanel.tag:1438:51: This attribute is not recognized.
<c:if test="<%= BeanUtils.getProperty(this,"bbar")!=null %>">
^--^
tree.treePanel.tag:1438:59: This attribute is not recognized.
<c:if test="<%= BeanUtils.getProperty(this,"bbar")!=null %>">
^--^
tree.treePanel.tag:1446:51: This attribute is not recognized.
<c:if test="<%= BeanUtils.getProperty(this,"buttons")!=null %>">
^-----^
tree.treePanel.tag:1446:62: This attribute is not recognized.
<c:if test="<%= BeanUtils.getProperty(this,"buttons")!=null %>">
^--^
tree.treePanel.tag:1454:51: This attribute is not recognized.
<c:if test="<%= BeanUtils.getProperty(this,"tools")!=null %>">
^---^
tree.treePanel.tag:1454:60: This attribute is not recognized.
<c:if test="<%= BeanUtils.getProperty(this,"tools")!=null %>">

Est-ce que quelqu'un utilise ces taglibs et arrive à les faire fonctionner et si oui comment please !!!

Merci d'avance