In your browser View Source and see if you are getting your JavaScript
right.
This is how I do it and most of the time my View Source tells me what is
wrong in my JavaScript.

Make sure your ClientID(s) are correct.
There might be syntax errors in your JavaScript

Also set you Browser to always report JavaScript errors,  you will be
surprised how many web pages out there with JavaScript errors that
programmers fail to see because there browser set up to NOT show errors.

the update panel does not support client events tied to the control via
html. this is becuase the browser doesnot support it: ex:

    div.innerHTML = "<button onclick='doClick()'>click me</button>";

the onclick event handler will not be hooker, nor will inline script work:
    div.innerHTML = "<script>alert('hi')</script>";

you will need to attach the onclick event via javascript the updatepanel
will run afterwards. using

ScriptManager.GetCurrent(Page).RegisterClientScriptBlock(Page,this.GetType(),"key1",
    "$get('mycontrolid').onclick=doclick;",
    true);

in this case, the script is sent down and the updatepanel code will do
an eval() of it.

of course in your case, you need to add one for for each row. the
databind would be handy for this, or your client script could walk the
dom and add the events.
   
-- bruce (sqlwork.com)