Activating button on Ajax reloaded div

[Zibo]

Hello.

I'm trying to add a single test record (a comment item) to my MySQL database.
So here are my sources of JSF2 project.

- main xhtml page:

<h:body>
	<h:panelGroup id="mainBlock" layout="block">
		<h:panelGroup id="header" layout="block">
			<h:graphicImage value="resources/logo.jpg" style=""/>
		</h:panelGroup><br/>
		<h:panelGroup id="menu" layout="block">
			<h:panelGrid columns="1" style="">
				<h:outputLabel value="MENU" style=""/>
                                <br/>
 
				<h:form>
					<h:commandLink action="#{navigationBean.requestPage}">
						<f:param name="requestedPage" value="news.xhtml"/>
						<f:ajax execute="@this" render="@none" />
						<f:ajax render=":content"/>
						<h:graphicImage value="resources/news.png"/>
					</h:commandLink>
                                        <br/><br/>
					<h:commandLink action="#{navigationBean.requestPage}">
						<f:param name="requestedPage" value="comments.xhtml"/>
						<f:ajax execute="@this" render="@none"/>
						<f:ajax render=":content"/>
						<h:graphicImage value="resources/comments.png"/>
					</h:commandLink>
					<h:commandLink action="#{navigationBean.requestPage}">
						<f:param name="requestedPage" value="login.xhtml"/>
						<f:ajax execute="@this" render="@none"/>
						<f:ajax render=":content"/>
						<h:graphicImage value="resources/login.png" style=""/>
					</h:commandLink>
				</h:form>
			</h:panelGrid>
		</h:panelGroup>
 
		<h:panelGroup id="content" layout="block">
			<ui:include src="#{navigationBean.viewedPage}"/>
		</h:panelGroup>
	</h:panelGroup>
</h:body>

- xhtml page where I try to add a comment into DB after clicking the button:

<h:dataTable id="table" value="#{db.commentsList}" var="c" style="">
	<h:column>
		<f:facet name="header">
			User
		</f:facet>
		#{c.user}
	</h:column>
	<h:column>
		<f:facet name="header">
			Comment
		</f:facet>
		#{c.content}
	</h:column>
	<h:column>
		<f:facet name="header">
			Date
		</f:facet>
		#{c.data}
	</h:column>
</h:dataTable>
<br/><br/>
 
<h:form>
	<h:commandButton action="#{db.addComment}" value="Submit"/>
</h:form>

- java code of my bean:

@ManagedBean(name = "db")
public class Database
{
	private List<Comment> commentsList;
        
         .....
 
        public void addComment()
	{
		Connection conn = null;
 
		try
		{
			Class.forName("com.mysql.jdbc.Driver").newInstance();
			conn = DriverManager.getConnection("jdbc:mysql:///jsfproject_db", "root", "pwd");
 
			PreparedStatement ps = conn.prepareStatement("INSERT INTO comments VALUES (null, 'test', cast('2000-01-01' AS date), 'test')");
			ps.executeUpdate();
 
			ps = conn.prepareStatement("SELECT user, content, data FROM comments");
			ResultSet results = ps.executeQuery();
 
			commentsList = new ArrayList<Comment>();
 
			while (results.next())
			{
				Comment com = new Comment();
				com.user = results.getString("user");
				com.content = results.getString("content");
				com.data = results.getDate("data");
				
				commentsList.add(com);
			}
		}
		catch (Exception ex)
		{
			Logger.getLogger(Database.class.getName()).log(Level.SEVERE, null, ex);
		} finally
		{
			try
			{
				conn.close();
			} catch (SQLException ex)
			{
				Logger.getLogger(Database.class.getName()).log(Level.SEVERE, null, ex);
			}
		}
	}
}

The double f:ajax tags in commandLink body are to solve a problem, where I had to double click the button to reload content div.

And now here comes similar problem:
After loading the page, the first click of comment adding button never works - nothing happens. I was adding some logging methods into the addComment method and it is not executed at all on first click. I suspect it's caused by my Ajax reloaded div code, because when I launch such button on a plain page, it works good.

Any suggestions how to fix my code? Alternatively are there other ways of realizing panel refreshing instead of using ui:include tag, which might be causing the problem here?