Rails - Jan 2006 - auto_link generating error (nil.gsub) in functional test

Hi everyone,

When running tests, I get this error for running auto_link on a set of
column data:

test_list(PersonnelControllerTest):
ActionView::TemplateError: You have a nil object when you didn''t expect
it!
The error occured while evaluating nil.gsub
    On line #28 of app/views/personnel/list.rhtml

    25:   <tr valign="top" class="<%= alternate_rows
%>">
    26:   <% display_columns = ["username",
"preferred_name", "email",
"title"] %>
    27:   <% display_columns.each do |column| %>
    28:           <td><%= auto_link(person.send(column))
%></td>
    29:         <% end %>
    30:     <td><%= link_to ''Details'', :action =>
''show'', :id => person %></td>
    31:   </tr>

Only one of the pieces of data ends up with a link (the email), so
this is probably bad design anyway.  How can I handle auto-linking the
email address in this situation?

Thanks,

Sean