A 709 is not even an income tax form. You mail it separately from a Form 1040. Mailed returns are not "accepted" or "rejected" the way e-files are. You will just have to wait for a human to open your envelope and enter your gift form into the system. Whenever you mail anything to the IRS, use a mailing service like certified mail so you will know that they received it.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
