Napster will be monitoring just what its competitor EMusic is doing with its new "acoustic fingerprint technology", which the company unleashed this week to stop Napster users from swapping its songs, Napster chief executive Hank Barry said Thursday. On Tuesday, music download site EMusic.com laid down the gauntlet, telling Napster users that it has developed a technology that can detect which EMusic files are being swapped among the 38 million Napster users. EMusic chief executive Gene Hoffman said the company flipped the switch after repeated attempts to get Napster to stop its users from swapping music downloaded from the EMusic site, which charges a monthly subscription rate or a per-song fee of 99 cents. But Barry countered with a prepared statement released late Tuesday, saying that Napster will be "reviewing EMusic's interaction with the Napster system" to see if it complies with Napster's own privacy policy. Hoffman claims the software -- which runs 24 hours a day, seven days a week and sends out warnings in instant messages to Napster users -- doesn't break any privacy rules. "We're not maintaining information about any consumer," Hoffman said. "We're hard-pressed to say we at EMusic have less of a right to look at your shared files than Napster users do." Barry had his own take on just what EMusic and Napster discussed in the six months or so before EMusic unleashed its "acoustic fingerprinting technology". Hoffman said Tuesday that EMusic offered Napster the same programming to use, but that the latter never got back to the company with an actual answer other than "we're looking into it." But Barry said in his prepared statement that the two sides did indeed meet and that Napster reviewed the software. But what EMusic unleashed on Tuesday, said Barry in his statement, "is different than what they have proposed to us previously," although the chief executive did not reveal the differences he's seen in the software. But the fingerprinting that EMusic is now using is both "not technologically feasible" nor consistent with the Digital Millennium Copyright Act, which governs copyright on the Internet, Barry said. Napster is being sued by all five major record labels, which allege that Napster is violating copyright laws. One of Napster's assertions is that a technology such as the one EMusic said it activated this week is not viable. Take me to the MP3 Special Have your say instantly, and see what others have said. Click on the TalkBack button and go to the ZDNet News forum. Let the editors know what you think in the Mailroom. And read what others have said.