Actor William Shatner's ex-wife is suing Star Trek's Capt. Kirk over frozen semen.

Shatner's second wife, Marcy Lafferty Shatner, is taking the Starship Enterprise commander to court, saying he broke an agreement they had over breeding privileges for three American saddlebred stallions.

Shatner claims that when they broke up in 1995, at a time when they co-owned several horses, the veteran actor agreed she could have one breeding privilege per calendar year.

But this year, instead of sending her "fresh cooled" semen for breeding purposes, the 72-year-old actor sent her frozen horse semen.

"That's just not good enough," said Lafferty's Kentucky-based lawyer, C. Thomas Ezzell.

"The frozen semen could be years old," he told The New York Post. "You never know. It's like a sperm bank. The chances of a successful impregnation are reduced."

The suit claims the frozen semen denied Lafferty the ability to breed her mare, Espere, to Sultan's Great Day, a champion harness winner, whose foals have gone for as much as $165,000.

Ezzell said his client had not calculated how much the frozen semen could cost her, "but it could be substantial."

"Potential buyers of the breeding privileges do not want the semen in frozen format," says Lafferty's lawsuit.

The Star Trek veteran and science-fiction author has owned central Kentucky horse farms since the mid-1980s and has a home in Lexington.

Ezzell said the actor had not yet responded to the lawsuit.