Hoping that an appropriate blow-over period will have occurred between now and the beginning of spring, Summit Entertainment has now set March 23 as the release date for The Beaver , starring Mel Gibson. Summit is proceeding cautiously. It had planned to release the Jodie Foster-directed movie (she also co-stars) this year but postponed it after the recordings of Gibson's venomous telephone conversations with his ex-girlfriend, OKSANA GRIGORIEVA, hit the media. The studio now plans to open the film on a Wednesday in a handful of theaters, then expand it nationally, depending on initial ticket sales, on April 8. But Gibson's personal life could very well doom the film's chances for success. It already has resulted in his losing a Cameo role in the upcoming The Hangover Part 2, and just today (Thursday) actress Winona Ryder is being quoted in GQ magazine as saying that she encountered a drunk Gibson at a party in 1995 who was spewing anti-gay and anti-Semitic remarks. Why has she waited until now to recount the incident? "No one believed me!" she told the magazine.