Performance Technologies (PTIX) warned that it expects to report second-quarter earnings of about 11 cents a share, well under the four-analyst estimate of 19 cents and matching the year-ago figure. The wireless telecom and networking products supplier cited a shipment delay and lower-than-expected orders from two major customers.

In other postclose news (earnings estimates from

First Call/Thomson Financial

; earnings reported on a diluted basis unless otherwise specified):

Earnings/revenue reports and previews

Autozone

(AZO) - Get Report

reported third-quarter earnings of 50 cents a share, a penny ahead of the 14-analyst estimate and up from the year-ago 39 cents.

Vintage Petroleum

(VPI)

said it will take a second-quarter charge of 25 cents a share for an adverse decision by an Argentine court in an oil-production royalty case. The 16-analyst estimate currently calls for Vintage to report operating earnings of 54 cents a share vs. the year-earlier 4 cents.

Offerings and stock actions

Activision

(ATVI) - Get Report

set a $5 million increase of its stock buyback program, in addition to the previously approved $10 million authorization.

Intira

(NTRA) - Get Report

withdrew its $104 million IPO, citing unfavorable market conditions.

RightStart.com

(TOTS)

, the online arm of children'e educational products retailer

Right Start

(RTST)

, has requested that the

Securities and Exchange Commission

withdraw its $69 million IPO, citing unfavorable market conditions.

Tyco's

(TYC)

TyCom

(TCM)

unit upped the size of its planned IPO to 43 million shares, slated to be priced in a range of $26 to $30 a share.

Miscellany

The

White House

said it canceled

President Clinton's

planned Sunday-night speech to the nation on the China trade bill. At least two major networks had refused to grant the president airtime.

FEI

(FEIC)

announced that CEO William Mooney will retire effective June 15.

As originally published, this story contained an error. Please see

Corrections and Clarifications.