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They may not be as unpredictable as Michael Jackson, but witnesses in the singer's child molestation case have surprised lawyers on both sides with unexpected testimony.

Flight attendant Cynthia Bell (search) had been expected to testify this past week that Jackson shared wine with his young accuser on an airplane trip — but she said no such thing.

Bell testified she served Jackson wine in a Diet Coke can but did not see the boy drink from it.

Prosecutors also thought Jesus Salas (search), the pop star's former house manager, would say he served wine to Jackson and several boys. But on the witness stand, Salas suddenly remembered he had also brought soda for the boys.

Jackson, 46, is on trial on charges of molesting a 13-year-old boy at his Neverland (search) ranch in 2003, and one of the counts alleges he plied his accuser with alcohol, but the testimony left prosecutors with no direct evidence to prove that allegation.

"The DA's come up empty-handed," said Jim Hammer, an analyst at Fox News and a former San Francisco prosecutor. "You shouldn't be surprised by your own witnesses."

The Jackson case has seen an unusual number of people change key aspects of their testimony or say something unexpected, said Loyola Law School (search) professor Laurie Levenson. It could be a sign that prosecutors are overwhelmed by the number of witnesses or by how quickly the case went to trial, she said.

"When you do last-minute preparation, you're more likely to have surprises," Levenson said.

Defense attorneys also have faced unexpected testimony. They had hoped comedian George Lopez would say the accuser once tried to con him out of $300 by claiming that Lopez took money from the boy's wallet. During testimony, however, Lopez accused the boy's father of orchestrating the scheme.

Prosecutors have occasionally looked frustrated as their witnesses strayed.

Jackson's accuser told a grand jury last year that the pop star once appeared nude in front of him and his brother and told them it was "natural."

But while testifying last month, the boy did not initially recall the statement. When prosecutor Tom Sneddon pressed the boy, asking if he recalled what he told the grand jury, defense attorney Thomas Mesereau Jr. accused Sneddon of coaching the witness.

"I agree," Superior Court Judge Rodney S. Melville (search) said.

"I can't refresh his memory?" Sneddon asked.

"Not if he says 'I can't recollect,"' the judge said.

"I can't recollect," the boy said.

Eventually, the boy was allowed to review his grand jury testimony and then said he remembered Jackson making the statement.

Several witnesses testified that they met with prosecutors only a day or two before taking the stand, suggesting they had little time to review earlier statements to sheriff's investigators, grand jurors or during lawsuits.

Salas seemed to catch prosecutor Gordon Auchincloss off guard when asked if he had served wine to Jackson and children. The former house manager said he did bring wine but also had brought soda for the children.

"When you talked to the Sheriff's Department about this, you never mentioned anything about any soda," Auchincloss said.

"It just flipped into my mind right now," Salas testified.