hi AlexanderBelov
great thanks for your post,
i tried to what you say, after all my example looks like :
1.DataBases.java

public class DataBases implements TreeNode {

 private Map databases = null;
 public Map getDatabases() {
 if (databases==null) {
 initData();
 }
 return this.databases;
 }
 public void setData(Object object) {
 }
 public void removeChild(Object object) {
 databases.remove(object);
 }
 public TreeNode getChild(Object id) {
 return (TreeNode) getDatabases().get(id);
 }
 public void addDatabase(DataBase database) {
 addChild(Long.toString(database.getId()),database);
 }
 public void addChild(Object identifier, TreeNode child) {
 getDatabases().put(identifier,child);
 child.setParent(this);
 }
 public void setParent(TreeNode treeNode) {
 }
 public boolean isLeaf() {
 return true;
 }
 public TreeNode getParent() {
 return null;
 }
 public Object getData() {
 return this;
 }
 public Iterator getChildren() {
 return getDatabases().entrySet().iterator();
 }
 private long nextId = 0;
 private long getNextId() {
 return nextId++;
 }
 public void initData(){
 databases = new HashMap();

 DataBase oracle = new DataBase(getNextId());
 oracle.setName("Oracle");

 DataBase iBMDB2 = new DataBase(getNextId());
 iBMDB2.setName("IBM DB2");

 DataBase msSql = new DataBase(getNextId());
 msSql.setName("MS SQL Server");

 DataBase postgreSQL = new DataBase(getNextId());
 postgreSQL.setName("Postgre SQL");

 DataBase mySQL = new DataBase(getNextId());
 mySQL.setName("My SQL");

 addDatabase(oracle);
 addDatabase(iBMDB2);
 addDatabase(msSql);
 addDatabase(postgreSQL);
 addDatabase(mySQL);
 }
 public String getType() {
 return "metadata";
 }
}

public class DataBase implements TreeNode{

 private static final long serialVersionUID = 7155620465939481885L;
 private long id;
 private String name;
 private DataBases databases;

 public DataBase(long id) {
 this.id = id;
 }

 public void setData(Object object) {
 }

 public void removeChild(Object object) {
 throw new UnsupportedOperationException("Database do not have children");
 }

 public TreeNode getChild(Object object) {
 throw new UnsupportedOperationException("Database do not have children");
 }

 public void addChild(Object object, TreeNode treeNode) {
 throw new UnsupportedOperationException("Database do not have children");
 }

 public void setParent(TreeNode treeNode) {
 this.databases = (DataBases) treeNode;
 }

 public boolean isLeaf() {
 return true;
 }

 public TreeNode getParent() {
 return databases;
 }

 public Object getData() {
 return this;
 }

 public Iterator getChildren() {
 throw new UnsupportedOperationException("Database do not have children");
 }

 public String getName() {
 return name;
 }

 public void setName(String name) {
 this.name = name;
 }

 public long getId() {
 return id;
 }
 public String getType(){
 return "database";
 }
}

<rich:tree rendered = "true" style="width:300px" value="#{database.data}" var="item" nodeFace="#{item.type}">
 <rich:treeNode type="metadata">
 <h:outputText value="#{item.type}" />
 </rich:treeNode>
 <rich:treeNode type="database">
 <h:outputText value="#{item.name}" />
 </rich:treeNode>
 </rich:tree>

and how i can use logging ?

i got this error on client side (JavaScript Error):

this.elements.contentTd has no properties
initialize()tree.js (line 2)
initialize("j_id77:j_id120", "j_id77:j_id120:input", "ajax", Object, function(), "")tree.js (line 2)
create()prototype.js (line 3)
[Break on this error] Richfaces.TreeSelectEvent="Richfaces.TreeSelectEvent";Richfaces.TreeExpandEvent=...

i did not understand what does it mean :(