The pilot was preparing his self-launching glider for a local flight at the uncontrolled airport. As he approached the hold short line for runway 11, he announced his position and intentions on the common traffic advisory frequency. He entered the runway and commenced the takeoff roll. At 40 knots, he observed another airplane taking off on runway 29 (opposite direction). He veered the glider to the right into the grass, and the landing gear struck a gopher hole. The right wing struck a runway sign and the glider came to rest. The glider pilot asked the other pilot if he heard his takeoff transmission, and the other pilot replied no, he did not have a radio in his airplane. A crown in the runway does not allow a full view of opposite direction traffic on runway 11/29. After the accident, the pilot reported that his glider club will post a marshaller with a radio with full view of the runway to provide an "all clear" before takeoff.