How to reference parent using some version variable

[Normandes Jr]

Hi,

   I would like to reference the parent at a child module using variable at
version.

   I would like to do this, because I have a lot of projects that are child
of parent. And if I change the version of parent, I will have to change all
modules.

   I tried this, but not working:

   <artifactId>my-child</artifactId>

   <parent>
        <artifactId>my-parent</artifactId>
        <groupId>group.my.parent</groupId>
        <version>${pom.version}</version>
    </parent>

   I am using maven 2.2.1.

   Any idea?

   Regards,

Junior.