(Augusta, Maine) Diane Sammer and her partner, Pam Dennis, were careful to sign papers giving Sammer power of attorney over Dennis’ affairs. Yet after Dennis died of a heart attack and her body was to be cremated, the undertaker refused to accept Sammer’s signature.

After some legal wrangling, Sammer signed a document to free the undertaker of any potential legal liability for taking away the remains of the woman with whom she had lived for 28 years.

“It was humiliating and just made an unbearable situation that much more so,” said Sammer, who’s from the coastal Maine town of Harpswell.

Sammer’s situation is one of many examples of how Maine law differentiates between straight and gay couples, said Jennifer Wriggins, a professor at the University of Maine School of Law.

Since 2004, Maine has had a domestic partner registry, which is supposed to grant some legal rights similar to those enjoyed by married couples. But it’s largely useless when it comes to wills, workers’ compensation, guardianship and retirement benefits, Wriggins said.

This week, the state House of Representatives is expected to take up a same-sex marriage bill that was endorsed by the state Senate. Democratic Gov. John Baldacci is undecided on the bill.

Vermont’s Legislature has enacted a law for gay marriage, and courts have ordered Massachusetts, Connecticut and Iowa to legalize it. The New Hampshire Senate and House have passed different versions of a gay-marriage bill. And some states have adopted civil union or domestic partnership laws to confer upon same-sex couples the rights associated with marriage.

The activity shows that states are eager to assert themselves on gay marriage, said Kimi King, a political science professor at the University of North Texas.

“You are going to see many other states weighing in on this issue,” said King, who foresees state actions until “a patchwork of laws is formed across the country.”

While Maine law has evolved to treat male and female spouses equally, there are distinctions in key areas of wills and probate between married couples and same-sex couples, according to a memorandum by family law attorney Michael Levey.

In traditional marriages, for example, a portion of the deceased’s estate goes to the surviving spouse if there’s no will. Even if the will excludes the surviving spouse, he or she is still entitled to about a third of the estate. Neither provision applies to same-sex couples.

Surviving spouses are protected from creditors. Maine law also requires spouses to support each other when in need, and a partner who fails to do so can face a court order. This doesn’t apply to same-sex couples.

Other examples of differences are cited in the memorandum:

-When a worker suffers a job-related death, workers’ compensation law says the surviving spouse shall receive 80 percent of the employee’s average weekly wage for nearly 10 years. That provision doesn’t apply to same-sex couples.

-State law says a spouse is considered appropriate to be a guardian for a disabled person, but same-sex partners have no such priority to appointment.

-State laws treat gay and straight couples who have children differently. For same-sex couples, there’s no assumption that the couple’s child is theirs.

“Same sex couples who are parents similarly may find the law’s refusal to recognize the marriage and family relationship to be stigmatizing and undermining,” the memorandum says.

A Maine gay marriage law could influence how same-sex couples are treated under some federal laws, says Wriggins’ memorandum. Social Security spousal benefits, for example, hinge on whether a state classifies someone as married. Federal law and agencies traditionally look to the states to define who qualifies as married, Wriggins said.

But King said how gay couples in states that allow same-sex marriages will be treated under federal programs is far from settled, and some cases are already in litigation.

“We’re universally,” King said, “in a gray area here.”