(Boston) Gay couples traveling overseas can now show passports that feature their married names, letting them take advantage of a little-noticed revision to State Department regulations that critics had feared would undermine the federal Defense of Marriage Act.

The notice of the change says that it does not mean the State Department is recognizing the validity of same-sex marriages and civil unions, but that it was to comply with an amendment to the Code of Federal Regulations that took effect in February 2008.

The name-change revision took effect May 27 in an addition to the State Department’s Foreign Affairs Manual. It allows same-sex couples to obtain passports under the names recognized by their state through their marriages or civil unions.

Keith and Al Toney, of Holden, learned of the change this week and expressed relief at the end of an effort that began in 2007, when Keith applied for a passport under his married name but was denied.

“We’ll probably be going back to Costa Rica in August, and just knowing that I don’t have to hand over a passport that I considered fraudulent … just knowing that I have an accurate passport, I feel like I can hold my head up high,” Keith Toney said.

The move is separate from steps Secretary of State Hillary Rodham Clinton took this week to grant some of the same benefits to the partners of gay diplomats as those available to spouses in heterosexual marriages.

Still, groups opposed to gay marriage criticized the name-change provision, saying it erodes the federal Defense of Marriage Act, which prohibits federal recognition of any same-sex partnerships.

“It’s an exercise that the current administration is using to try to nibble away at the Defense of Marriage Act,” said Kris Mineau, president of the Massachusetts Family Institute.

“There’s no doubt that President Obama has made a strong commitment to repeal the DOMA … and it will take an act of Congress to do so,” Mineau said. “He cannot circumvent the law, but he attempts to do so not head-on, but in an oblique approach.”

Obama said he wants to see the Defense of Marriage Act repealed. But he’s been heavily criticized by gay rights groups for not moving quickly enough on his campaign promises to expand gay rights.

Evan Wolfson, executive director of Freedom to Marry, a New York-based group that campaigns nationally for gay marriage rights, said the change in passport regulations is a “very small step in the right direction,” but falls “far short of the work that needs to happen to keep the federal government from discriminating against gay couples across the country.”

The Toneys got married in 2004, shortly after Massachusetts became the first state to legalize same-sex marriage. Keith, whose unmarried name is Fitzpatrick, was rejected when he applied for a passport as Keith Toney. The passport agency cited the Defense of Marriage Act.

Keith Toney was forced to get a passport in his old name so he could travel with his spouse and daughter to Costa Rica, where the family owns a vacation home, he said.

During previous trips, he said, he was repeatedly questioned about why the name on his passport differed from the name on his other forms of identification, including his Massachusetts driver’s license, which had his married name.

“It was degrading, it really was,” he said.

The couple later joined a lawsuit challenging the act filed by the Boston-based Gay & Lesbian Advocates & Defenders.

GLAD received a letter from the Justice Department this week, informing the group of the change and inviting Keith Toney to submit a passport renewal application with his married name. He plans to submit his application to the Boston Passport Agency on Monday.

The separate changes instituted this week by the State Department include the right of domestic partners to hold diplomatic passports, government-paid travel to and from foreign posts, the use of U.S. medical facilities abroad, eligibility for U.S. government emergency evacuations, and training at the State Department’s Foreign Service Institute.

Clinton announced the measures after Obama’s decision on Wednesday to grant some benefits to the same-sex partners of gay federal employees.