TRENTON, N.J. (AP) – New Jersey’s governor signed legislation Thursday giving gay couples all the rights and responsibilities of marriage allowed under state law – but not the title.

When the law goes into effect Feb. 19, New Jersey will become the third state offering civil unions to gay couples and the fifth allowing gay couples some version of marriage.

Connecticut and Vermont also offer civil unions for gay couples, while Massachusetts allows gay couples to marry, and California has domestic partnerships that bring full marriage rights under state law.

“We must recognize that many gay and lesbian couples in New Jersey are in committed relationships and deserve the same benefits and rights as every other family in this state,” Gov. Corzine said in signing the legislation.

The Legislature passed the civil unions bill on Dec. 14 in response to a state Supreme Court order that gay couples be granted the same rights as married couples. The court in October gave lawmakers six months to act but left it to them to decide whether to call the unions “marriage” or something else.

Gay couples welcomed the new law, but argue not calling it “marriage” creates a different, inferior institution. Even some same-sex couples who attended the bill signing remained lukewarm about the law.

“It’s a step forward, but it’s not true equality,” said Veronica Hoff, 52, of Mount Laurel, as she stood with her partner.

The civil unions law grants gay couples adoption, inheritance, hospital visitation and medical decision-making rights and the right not to testify against a partner in state court.

They won’t be entitled to the same benefits as married couples in the eyes of the federal government because of 1996 law that defines marriage as between a man and a woman. Gay partners won’t be able to collect deceased partners’ Social Security benefits, for example, said family lawyer Felice T. Londa, who represents many same-sex couples.

Social conservative groups and some lawmakers opposed the measure, saying it brings gay relationships too close to marriage, but it easily passed the Legislature.

“It’s same-sex marriage without the title,” said John Tomicki, president of the New Jersey Coalition to Preserve and Protect Marriage. “It uproots the cardinal values of our culture.”

He said opponents would push for a constitutional amendment that would ban same-sex unions in New Jersey, no matter what they’re called.

“Let the voters decide that marriage is defined as a union of one man and one woman,” Mr. Tomicki said.

Democrats who control the Legislature have said they have no plans to consider such a proposal.