IRA Contribution

The Turbo Tax questionnaire says that my son cannot contribute to an IRA since all of his income is categorized as "Other Income" (Schedule 1 - Line 8z).  He has a full scholarship and a monthly stipend (the "Other Income") for Grad School.  I spoke with the IRS and they agree that he can contribute per Publication 590-A.  However, the software includes a penalty when he includes the contribution.  Any thoughts?  Thanks!