I have come across a problem with the sql.pkg

After I migrated my development workspace from 17.0 to 18.0, I am getting a whole bunch of error messages like following:

Code:
Command not found SQLOPEN
Command not found SQLEXECDIRECT
The problem comes up inside a business process. The "Use sql.pkg" is at the very top of the business process and when I click on "Go to Definition" it opens the package and finds the command it claims not to have.

Did anyone run into the same/similar problem and can help me on this?