[Zope] How can I customize the propertysheet management interface?

[Fabio Rolando]

Hi everybody.
I have a ZClass with a propertysheet with a number of properties. I have 
created my own MyZClass_addForm and MyZClass_add in order to give users an 
interface to handle the creation of instances of MyZClass and the 
definition of the properties in the way I want them to do it. Now I would 
like to use a similar interface when the user needs to modify the 
properties, but I can not figure out how I can modify the 
.../propertysheets/my_propertysheet/manage page.
I hope you can help me. Than you in advance.
Regards. Fabio