Former WorldCom Inc. (search) CEO Bernard Ebbers (search) derided his finance chief as a "short man" and criticized him for being too conservative when he spoke with stock analysts about the company's outlook, according to testimony at his fraud trial on Tuesday.

Scott Hamilton, a former investor relations manager at WorldCom who is one of the final witnesses for the prosecution, also described Ebbers to jurors as an "intimidating" boss with a temper.

Click here to read the indictment against Bernard Ebbers

In one incident, Hamilton testified, he received an e-mail from a "crazy" person with an illegitimate offer to buy the company. Rather than bringing the e-mail to Ebbers' attention, Hamilton forwarded it to the company's lawyers.

When Ebbers found out about it, "he was very upset" that he had not been immediately alerted to the e-mail, Hamilton testified.

"He cursed and told me not to ever f'ing do that again," Hamilton told jurors. "He told me if there was ever an f'ing offer to buy the company, I'd better take it directly to him."

Hamilton also said Ebbers -- charged with fraud in connection with WorldCom's $11 billion accounting scandal -- often ridiculed Chief Financial Officer Scott Sullivan (search).

"He talked regularly about Sullivan's stature, calling him 'short man' behind his back," Hamilton said. At other times Ebbers would criticize the finance chief because "he felt Scott Sullivan was too conservative in guiding analysts" about the company's earnings.

Federal prosecutors have argued to the jury that Ebbers was obsessed with the company's earnings guidance, and refused to lower it even when WorldCom's finances began to deteriorate.

Instead, they charge, he orchestrated a massive accounting fraud that eventually involved hiding billions of dollars in expenses so the company's earnings could meet Wall Street's expectations.

Ebbers insisted on meeting those estimates, prosecutors charge, because he was concerned that any failure would result in a steep drop in WorldCom stock -- which made up the bulk of his personal wealth and with which he secured personal loans of more than $400 million.

Investigators uncovered the accounting fraud in 2002 and the company was forced to file for bankruptcy protection. Six senior executives were eventually indicted for fraud.

Ebbers is the only one of those executives to plead not guilty. He faces up to 85 years in prison if convicted on all counts.