Z-Tel Technologies, a CLEC based in Tampa, Florida, reported substantially improved financial performance over the second half of 2002, which it attributed to operating improvements, improving margins, growing active line counts and lower bad debt expense. For Q4, Z-Tel reported revenues of $57.0 million, compared to $59.1 million for the prior year period, and EBITDA (earnings before interest, taxes, depreciation and amortization) of $2.2 million, compared to negative $3.9 million for the same period in 2001. Net loss for the fourth quarter...