How to create an extra field in the profile module to only accept the numeric values? I am creating extra fields in the user registration form. for this I am using the profile module.

In this module there is no option form creating a text field which should only accept the numeric values just like in drupal 7.

So how will I create such field in the user registration form?

Any idea?
Install CCK module. Enable the number module that comes with CCK module. Once you enable the module you can able to add integer field to the Profile Content type if you are using content_profile module to add fields to registration.

See the screenshow below that i just got to do it using CCK, Number, Content Profile module in Drupal 6.