Beginner question of AjaxForm and tacos table

[yinli . xiao]

Hi everyone,
I am a beginning learner of tacos. I had little experience with Tapestry. 
When I use tapestry table component with ordinary form, whenever I sort 
the table or go to another page, the whole page re-renders. To keep 
persist information in the form, I have to add tag @Persist("client") 
everywhere. 
The motivation I get from tacos is that I can sort the table without 
refreshing the page, neither the form. I tried the table demo on the 
project homepage. It indeed doesn't refresh the page. I copied the source 
code to my machine and tried to build the same page. But the page still 
re-renders when I sort the page when I use tacos:Table with AjaxForm. I 
looked into the generated html code. I found that the sort link is 
actually an AjaxDirectLink. 
<td><a 
href="/ajaxdirect.svc?component=tableColumnComponent.linkColumn&amp;container=tacos%3ASimpleTableColumnPage&amp;page=pages%2FtestTable&amp;rand=-407102156&amp;session=T&amp;sp=Apages%2FtestTable%2CnoFormTable.tableView&amp;sp=SdisplayLanguage&amp;updatedirect=false&amp;updateid=noFormTable.tableSection"
 
onclick="return tacos.defaultLinkAction({targetLink: this, url: this.href, 
processScripts: true, effects: {'highlight': {'any': '[255,255,184], 500, 
500'}}})" id="linkColumn_1">Language</a></td>

I have already spent two days on this example. Can anyone tell me what I 
did wrong or missed out? Thank you very much! If anyone can explain me how 
the AjaxDirectLink behaves, it is as helpful as solving the problem. 
Thanks again!