[Zope] More dtml-in sequenceing and cocatenation

I have a statment which outputs a sequence of form checkbox string pairs, from a MySQL source: <dtml-in SQL_getMath> <input type="checkbox" name="dance_<dtml-var sequence-number>" value="1" <dtml-if expr="'math_' + _['sequence-number'] == 1"> checked </dtml-if>> </dtml-in> This does not work quite right. What i need is to cocatenate, in the dtml-if expr, the string 'math_' with the number generated by sequence number in the loop. Based on that evaluation, the checkbox is checked or not. Any ideas on how to get this working? I can't seem to make much sense of the Zope Book explanation. Harlow Pinson Indepth Learning Email: hpinson@indepthl.com Web: http://www.indepthl.com Voice: 505-994-2135 FAX: 208-475-7678