SSA-1099 SM - impossible to file electronically when no W-2 wages are reported

When I file my SSA-1099 SM disability alone with no other W-2 wages to be reported, the taxable and adjusted income (7a, 8a) are left blank, hence I can not file my tax return electronically. Is this behavior by design or is there a way around it. This would make Turbo Tax completely useless for electronic filing when only SSA-1099 is reported..