jsf datatable problem with var attribute

While developing a small jsf application with datatable I am having following problem with this error

The method setVar(String) in the type DataTableTag is not applicable for the arguments (JspValueExpression)

in my jsp page i have following code fragment

<h:dataTable id="dt1" value="#{dbdata.empno}" var="item" bgcolor="#F1F1F1" border="10" cellpadding="5" cellspacing="3" rows="4" width="50%" dir="LTR" frame="hsides" rules="all" summary="This is a JSF code to create dataTable." >

in my java file i have following 2 code fragments--

while (rst.next())
{    
 empno.add(i++,new perInfo(rst.getString(1)));
}

public class perI开发者_JAVA百科nfo {
    String uname;

    public perInfo(String firstName) {
        this.uname = uname;
    }

    public String getUname() {
        return uname;
    }
}

the data is coming fine from database.

I have found that "var" attribute is giving problem

can you please advise

Looks like you ran into this bug:

Bug 41912 - JSF datatable does not work on tomcat 6.0.9

Regarding the comments on this page a possible workaround would be changing the combination of server and/or jsf version.

Sounds like you're trying to send a String to a relational database when it's expecting another type, like Date or number, to a particular table and column.

HTTP form elements only know about Strings. You should be validating and binding values from the UI on the server side before persisting them in a database.