An activist who led the repeal of “don't ask, don't tell” praised the military Tuesday for a smooth transition to openly gay service, but said his group wants same-sex couples to receive benefits now given only to heterosexuals.

“It's a denial of equal protection under the Constitution,” said Aubrey Sarvis, 65, executive director of Servicemembers Legal Defense Network and a one-time Army infantryman, in San Antonio for a fundraising event. “That's why it's an equal-protection constitutional challenge.”

SLDN last week filed a suit in Boston on behalf of eight active-duty, reserve and retired troops that challenges the constitutionality of the Defense of Marriage Act.

The law forbids the Pentagon from extending certain benefits to anyone but married heterosexual couples. SLDN also wants to change three provisions of federal law that define who a spouse is, he said.

“Don't ask, don't tell” was repealed Sept. 20. But Pentagon spokeswoman Eileen Lainez confirmed that federal law bars the extension of some benefits, including medical care, housing and family support.

Other benefits, including designating a beneficiary, were always open to troops, Lainez said, “but some members may have been reticent to designate their same-sex partners.”

DoMA defines marriage as “a legal union between one man and one woman.” The term “refers only to a person of the opposite sex who is a husband or a wife” under the 1996 law, which President Barack Obama has sought to repeal. Republicans generally support it and opposed the end of don't ask, don't tell.

Joshua Snyder, whose husband, Army Reserve Capt. Stephen Hill, is returning home from Tikrit, said they are being denied “basically any benefits that the Army currently offers to spouses” — even counseling.

Hill, a Desert Storm veteran, became famous after telling Republican candidates in a video that he “had to lie about who I was” when deploying to Iraq last year. Some audience members at the debate, held in September, booed him.

“We're recognized by the District of Columbia as a married couple,” said Snyder, 31, of Columbus, Ohio, “and while I understand where some people may have their points of view, if it's legal — if our marriage is recognized by a state — it shouldn't be blocked.”

Sarvis said his group is working with the Pentagon to allow some former gay, lesbian and bisexual troops to return to uniform. While the Defense Department allows that, he warned that many of the roughly 14,000 troops thrown out of the services will be excluded by such things as age restrictions.

“Quite frankly,” Sarvis said, “I don't know that we're going to see a huge number of reinstatements.”