On Dec. 25, Rod Shapiro and Pat Wong will exchange Christmas and Chanukah gifts spread under a seven-foot Christmas tree. They will listen to carols sung by Johnny Mathis and Chanukah songs by the Klezmatics.

In the evening, this interfaith couple in their mid-50s, married two years, will light the menorah and invite friends to stop by their Long Beach home.

Welcome to Chrismukkah 2005, a holiday that offers greeting cards that feature a reindeer with menorah antlers and recipes for Gefilte Goose and Kris Kringle Kugel in “The Merry Mish Mash Holiday Cookbook.” Christmas tree ornaments decorated with Stars of David abound, as well as a children’s book called, “Blintzes for Blitzen.”

For Shapiro, who describes himself as culturally Jewish, Chrismukkah is a light-hearted solution to the familial conflicts that interfaith couples often face. “Personally, I think that more and more people should embrace their similarities and tolerate their differences, and Chrismukkah is a holiday that allows couples to do that,” he said.

But for others, who won’t be wishing their interfaith family and friends a Merry Mazel Tov, Chrismukkah is a superficial and commercial pseudo-holiday that presents multiple problems. And it’s compounded this year by Chanukah and Christmas coinciding on the same day, an every-19-year occurrence.

In fact, Chrismukkah created enough of a stir last year that the independent Catholic League and the New York Board of Rabbis issued a joint statement condemning it as shameful plagiarism and an insult to both Christians and Jews. The two groups will likely issue another statement this year.

“The criticism still stands,” said the executive vice president of the New York Board of Rabbis, Rabbi Joseph Potasnik. “I just feel it’s inappropriate to take two very distinct holidays that belong to two different faith groups and to synthesize them into one. It doesn’t respect the integrity of either one.”

And while the Board of Rabbis of Southern California will not be putting out a similar statement, Executive Vice President Mark Diamond said, “In the strongest possible terms, we would urge families and individuals not to participate in and not to sponsor these Chrismukkah festivities.”

Chrismukkah first jumped into public consciousness in a episode of the Fox TV show, “The OC,” on Dec. 3, 2003, where the main character, Seth Cohen, the son of a Jewish father and Protestant mother, decided that interfaith families should no longer have to choose between Christmas and Chanukah.

“I created the greatest superholiday known to mankind, drawing on the best that Judaism and Christianity have to offer,” he declared.

And while Chrismukkah may not yet have lived up to Cohen’s prime-time expectations, this hybrid celebration was featured for the third time on “The OC” on Dec. 15, in an episode titled, “The Chrismukkah Bar Mitz-vahkkah.”

So is Chrismukkah nothing more than a made-for-TV, faddish, one-size-fits-all holiday that will fade from memory faster than Cabbage Patch Kids and Tickle-Me-Elmo? Or is it a more sinister creation that threatens to dilute the religious significance of two distinct holidays even further, trivializing them and confounding children’s sense of religious identity?

This melding and mingling of customs is nothing new. Historians trace it back to the Jewish Christians who lived in the first century C.E. And interfaith couples for ages have been quietly celebrating both holidays. Weinukkah, for example, the German celebration of both Christmas, or Weihnachten, and Chanukah, is the subject of a current exhibit in the Jewish Museum of Berlin through Jan. 29.

Perhaps out of a drive for assimilation, perhaps a desire not to be deprived of a lovely tradition, albeit not their own, generations of Jews, particularly German Jews, in this country have put up Christmas trees in their homes and called them Chanukah bushes.

Meanwhile, the number of interfaith families has continued to increase. The National Jewish Population Survey 2000-2001 counts 5.2 million Jews in the United States, with 47 percent of those, since 1996, marrying non-Jewish spouses.

And while estimates of the total number of interfaith couples widely vary, sociologist Bruce Phillips, professor of Jewish communal service at Hebrew Union College-Jewish Institute of Religion in Los Angeles, calculates the number at 624,000.

For these families, Edmund Case, president and publisher of InterfaithFamily.com, a nonprofit online resource for interfaith families, opposes combining elements of the two holidays.

His organization advocates raising the children of interfaith families as Jews, but he sees no problem in their participating in Christmas celebrations. “It doesn’t mean the kids won’t be Jewish; it doesn’t mean they’re rejecting Judaism,” he said.

In the Second Annual December Dilemma Survey sponsored by InterfaithFamily.com, two-thirds of the almost 400 self-selected respondents indicated that they planned to keep holiday celebrations separate. Additionally, 78 percent thought Chrismukkah a bad idea, while only 6 percent applauded the concept.

The Opper family of North Easton, Mass., hosts an annual Chanukah party, with latkes, cookies and games of dreidel. They also hold a separate Christmas celebration that includes such family traditions as lighting the tree, drinking hot chocolate and egg nog and making a gingerbread house.

“You lose the tradition and history of both of them trying to make a Chanukah bush out of a Christmas tree,” said Cheryl Opper, a practicing Protestant who, along with her husband, Neal, is raising their daughter Jewish.

And for 78 percent of the families responding to the InterfaithFamily.com survey, the Christmas celebrations are more secular than religious. Betty Bildner, who is Jewish, and John Power, a nonpracticing Catholic, have raised their three children Jewish, a decision made before they were married.

The Encino family celebrates Chanukah, but they also have a tree and a separate Christmas observance. For them, “Christmas is about giving and sharing and about getting together as a family,” Bildner said.

And to her husband, it’s a reminder of one of the happiest days of his childhood.

But for many families the distinctions are more blurry, and decisions regarding religious upbringing are often ignored until a child enters the picture. This was certainly the case for Ron Gompertz.

Gompertz, who describes himself as “a typical bar mitzvah boy from New York City,” is the son of Holocaust survivors but grew up with a Chanukah bush in the house. His wife, Michelle, the daughter of a Church of Christ minister, identifies more with Buddhism and atheism than anything. But it wasn’t until two and a half years ago, when their daughter, Minna, was born, that Gompertz, now 52, and his wife started thinking about religious issues.

As a result, the family moved to Bozeman, Mont., where in 2004 Gompertz created and launched Chrismukkah Web site (www.chrismukkah.com), which he first conceptualized as a way to make light of his own intermarriage.

The Web site, the subject of a current trademark conflict with Warner Bros., which produces “The OC,” serves as an online store to sell Chrismukkah cards and merchandise. It’s also a forum to publish Gompertz’ reflections on the subject, which range from whimsical to subversive, questioning the role of religion and God in the world.

“We celebrate Christmas and Chanukah separately, but laid over that is this metaphorical notion of Chrismukkah. We think about peace, love and brotherhood. It’s an attempt to reconcile rather than compete,” he said.

That concept works for Vanessa Hernandez and her husband, Joe Nierenberg, who are raising their children, 10 and 7, both Catholic and Jewish and who decorate their Oakland home with elements of both holidays. Stockings, for example, hang from a mantle that displays a menorah and dreidels.

“Chrismukkah is a trendy word and we don’t use it, but we definitely intermingle,” she said. “We do it out of respect for each other and being true to who we are.”

Gompertz’ rabbi, Allen Secher of Temple Shalom in Bozeman, supports such efforts. He sees no problem in commingling the holidays as long as the celebration doesn’t become obscene, such as people doing the hora around a Christmas tree.

But most rabbis disapprove.

“You cannot mix hot cross buns with latkes,” said Rabbi Harold Schulweis of Valley Beth Shalom in Encino. He is especially concerned with the misappropriation and misunderstanding of the holiday symbols, such as the evergreen tree, which represents the eternity of Jesus.

And it’s not only the rabbis who are troubled. The Rev. Paul Keenan, director of radio ministry for the Archdiocese of New York, said, “My real desire in all of this is to see Jews celebrate their holiday of Chanukah in as full and rich a spiritual way as they can and to be proud of that without feeling a need to adopt ours.”

Commercially, Chrismukkah might be gaining some ground. Gompertz reported that sales on his Web site are running about double of last year’s. He expects to sell about 75,000 Chrismukkah cards, with “Good Cheer With a Schmear,” a picture of four bagels with cream cheese, this year’s top seller. Still, “It’s a very small microgarage business,” he admitted.

And Elise Okrend, creator of MixedBlessing interfaith and multicultural cards, a retail and Internet business based in Raleigh, N.C., estimates sales of more than 350,000 cards this year, up from about 12,000 when she and her husband, Philip, founded the company about 15 years ago.

But spiritually, Chrismukkah remains a mystery.

“Why have any mishmash?” asked Schulweis, wondering what is drawing people, even in small numbers, to this celebration or concept, however misguided and misinformed.

“They’re looking for something, but they’re totally ignorant,” he mused.

Gompertz expressed surprise at last year’s vehement anti-Chrismukkah backlash by talk-show radio hosts and Jewish organizations.

“I’m a Jew and I’m a good Jew,” he professed.

Perhaps that’s why he’s been seriously researching the history of his European relatives. And perhaps that’s also why, during the past year, he and his wife made the decision to raise their daughter as a Jew.

Maybe that’s the real meaning — and miracle — of Chrismukkah.