(FORTUNE Small Business) – As the soldiers of the 428th transportation Company, a National Guard unit, prepared to ship out for Iraq from their base at Fort Riley, Kan., a few months ago, they heard some disturbing stories about the equipment they would be using. Troops already in Iraq told them that the armor on standard Army Humvees was not thick enough to protect against the many small explosives planted by guerrillas in the country's streets and roads. Too many soldiers, the Guardsmen were told, were coming home maimed or in body bags.

That's where two small-business owners stepped in. Reid Millard, 44, a funeral-home owner in Jefferson City, Mo., heard of the injuries from friends in the 428th, who asked whether he could help raise money to armor the vehicles. He said he would do better than that: He volunteered to buy enough quarter-inch steel plating to protect 72 Humvees and trucks used by the 428th, at a cost of $4,000. Then he phoned a friend in town, Virgil Kirkweg, 57, the co-owner of Industrial Enterprises, a sheet-metal fabricator, and asked him to cut the plating so that it would fit inside the floorboards and doors of the vehicles. Kirkweg said he and his workers would be glad to help.

In just three days Kirkweg's shop cut enough steel to fit each of the Humvees with 180 pounds of extra armor. The work was worth $15,900, mostly in labor. "The soldiers were speechless," Kirkweg says. "But what were we supposed to do--let them go without it?"

The Pentagon, however, had yet to weigh in. A week after the job was finished, with the Humvees and trucks already shipped to Iraq and the soldiers of the 428th waiting to follow from their base in Fort Riley, word came down that the Army considered the steel unauthorized equipment, meaning it had to be officially tested and approved before being sent into Iraq. The soldiers were discouraged--and Millard was furious. "Here you've got some guys trying to be entrepreneurial, trying to protect their comrades," he says, "and you're not gonna let them do it?"

He fired off a letter to the judge advocate's office in Fort Riley (with copies to the White House, Secretary of Defense, and Missouri congressional delegation). Millard's letter laid out the choice, as he saw it, for a military commander receiving 13,000 pounds of donated steel: make prosthetic limbs for the wounded and caskets for the dead--or affix it to the vehicles. Three days later the 428th was cleared to take its extra armor to Iraq.

The unit departed in mid-February. There is as yet no word on how the steel plates are holding up. But the Missouri entrepreneurs' can-do attitude is winning them fans. Kirkweg recently got a call from a woman in Fort Hood, Texas, asking if he would make armor plates for the Humvees in her son's unit. He agreed, but said this time he would call the Pentagon first.