How to add a workflow variable to 100 different workflows?

I need to add a workflow variable $$ABCD to 100 different workflows. Is there a way I can achieve it without modifying individual workflows? I want to save some effort here.

Solution

It is not possible to mass-edit workflows (or any other objects in PowerCenter). The only way is to export your workflows, edit the XMLs (can be done via script) and import them back.