Hi,
if I understood you, you are trying to do this:
- export current SEP package
- update the defs in the SEP package
- import this updated package back into the SEPM
If correct, I don't see reasons for doing it, you will need to export the package again to use it (even the deployment wizards do it at least in the temporary folders).
With the article linked below you will:
- export current SEP package as non single executable file
- update the defs in the SEP package
- make the up-to-date package created above into a single executable file, hence ready for usage without having to import it in and export it from the console again.
http://www.symantec.com/docs/TECH104779