Specifying %{variable} in control file for use in post inst?

[Ignacio Valdes <ivaldes@hal-pc.org>]

Hi, I want to define a variable such as package_initials in control
file and be able to access %{package_initials} in postinst file. Do I
define it in control file as:

XC-package_initials: the_initials

or some other way?

-- IV