The National Science Foundation's new Grant Proposal Guide, which is effective this month, requires that any proposal requesting funding for postdoctoral researchers must include a discussion of mentoring activities to be provided to the postdocs.
Repeat: This is not optional. Include a section on mentoring your postdoc in your 15-page project description or prepare to have the proposal returned without review. Click on the headline to view the portion of the GPG that sets forth the new requirement. Scroll down to "Proposal Contents," Section C.2.d.i.