Design Guidance Needed plz....

Hi Everybody

There is one table named HRMPosition. This table is part of HRM module. I am developing a module for Axapta in which requirement is like this.

If HRM module is installed on client machine use HRMPosition table in our module.
If HRM module is not installed make our own table with similar kind of structure and use that.

How can I handle such a situation?? What should I do??

I really need help. Thanks in advance.