[Zope] variable

[josh on]

Hello,

I have a line of code which is meant to tkae an integer variable (vchildren)
passed to the page through a hidden form.

I have a line of code which goes:

<dtml-var "_.chr(vchildren+97)">

and it returns an error message of which this is part:

File C:\Program Files\ZopeJosh01\lib\python\DocumentTemplate\DT_Util.py,
line 335, in eval
    (Object: _.chr(vchildren+97))
    (Info: vchildren)
  File <string>, line 0, in ?
TypeError: (see above)

The value of the variable is 0

josh