'Beginning in 2005, the IRS started the process of trying to change the rules around these tax shelters and simultaneously is in the process of extracting taxes on a retroactive basis from companies who have used these types of tax shelters,' Munster said.

'For us, it doesn't really make a difference,' said Dong Jin Kim, senior Unix systems administrator for worldwide information systems at Eastman Kodak Co. in Rochester, N.Y. 'Whatever happens to Symantec, we'll continue to use Veritas, because that's what we depend on.'

'We're still happy with everything we've used and continue to do what we've done before,' said Joe Kvidera, a consultant at Procedo Inc. who works for a large financial services company.