Control Panel Required Fields Date Entry, Date Expiration and etc

I’m in the process of porting “JB_Require_Expiry” over to EE 2.0. I have 80% of done and it is working correctly.

The basic functionally of module allows for the “Expiration Date” to be set as required field. Currently I am using “$this->EE->output->show_user_error” to display the error.

There are several drawbacks to this method: 1. Error is displayed on a separate page instead of inline. Would like it to work like the error for the title. 2. Does not allow to add an red “asterisk” to be added next to the field.

My question:

1. Is it possible to “hook” into the built in error systems for the control panel, if so how do you display the error inline, and how do you indicate that the field is required?