Modify customized App Intergrator

I added some custom parameters in a customized application intergrator. I imported the modified par file into the portal (7.0 SP12). The existing system definition using the customized application intergrator does not show the new parameters - if I create a new system from the same customized application intergrator par file the new parameters show.

Do I need to restart the portal to see the new parameters on the existing system definition?

Regards,

Diane