[Zope-CMF] how to personalize plone personalize_form?

[Wostenberg]

I'm collecting extra membership data -- a cellphone number. I 
successfully modified portal_memberdata based on a zope labs cookbook 
item, and fixed up the plone join_form to collect and store the new 
property cellphoneNumber.

But I'm having no joy  modifying the Plone skin personalize_form so 
members can change it later.  What I've done is base it on how 
personalize_form does email:

                <div class="field" tal:attributes="class 
python:test(error_email, 'field error', 'field')">
                   
                    <div tal:condition="error_email"
                         tal:replace="structure string:$error_email <br 
/>" />                     
                   
                    <input type="text"
                           name="email"
                           size="25"
                           tabindex="1"
                           value="member.email html_quote"
                           onfocus="formtooltip('new_email_help',1)"
                           onblur="formtooltip('new_email_help',0)"
                           tal:attributes="value email"
                           />
                </div>

for cellphone
            <div class="field"
                  tal:attributes="class python:test(error_cellNumber, 
'field error', 'field')" >

                <div  tal:condition="error_cellNumber"
                      tal:replace="structure string:$error_cellNumber<br 
/>" />

                <input type="text"
                       name="cellNumber"
                       size="20"
                       value="member.cellNumber html_quote"
                       tal:attributes="value cellNumber"
                       tabindex="4"
                       onfocus="formtooltip('cellNumber_help',1)"
                       onblur="formtooltip('cellNumber_help',0)" />
            </div>


The result is the cellphone shows blank on this form, and gets erased if 
the personalize_form is submitted.    See input tag 
value="member.cellNumber html_quote"? Even if I replace it with 
value="member.email" it is blank. So I'm confused on the connections 
between name=X, value="member.X", and tal:attributes="value X" . Any 
guidance warmly appreciated!

-Alan Wostenberg http://www.psalmweaver.com