Microsoft and RealNetworks went at it again Friday, continuing Thursday's dispute over whether Microsoft intentionally broke RealNetwork's streaming media player. RealNetworks came out swinging in a phone conference with press and analysts Friday, lining up two additional software vendors who echoed Real's claims that Microsoft's multimedia technologies break their products. Meanwhile, Microsoft touted the findings of ZD Virtual Labs (part of Ziff-Davis Inc.'s PC Magazine franchise), which backed Microsoft's claims that the failure of RealNetworks' "G2" RealPlayer beta to function properly is due to a bug in RealNetwork's own code. "Microsoft is right," said Larry Seltzer, technical director of ZD Virtual Labs. "It's completely unjustifiable for RealNetworks to say that Microsoft has changed something that broke the G2 player." Seltzer said G2 breaks only in fairly limited scenarios. "It's only with certain videos that aren't already embedded and only if the G2 beta is not installed over a previous version of RealNetworks' RealPlayer." Thursday, RealNetworks CEO Rob Glaser told a Senate Judiciary Committee panel that Microsoft intentionally broke its rival's streaming media player. Glaser cited the incident as an example of Microsoft's intention to stifle innovation. Microsoft retorted late Thursday by posting to its Web site a white paper that claimed that G2 broke only with Netscape's Navigator, not with Microsoft's Internet Explorer -- and as a result of a bug in G2, not a problem with Microsoft's Media Player. "Real stands behind our testimony 100 percent," said Glaser during Friday's conference call. "The Windows Player breaks our player in 10 out of 16 configuration scenarios." He said that both Navigator and Internet Explorer, both gold and beta code, and both free and $30 versions of RealNetworks' player, break when used in conjunction with Microsoft's player on a variety of platforms. "This is not just a dispute between us and Microsoft," said Glaser added. "Microsoft Media Player disables a lot of companies' technologies." During the conference call, Shawn Cooney, a founder and principal with Digital Bitcast Corp., seconded Glaser's claims, saying that "Microsoft's products run roughshod over certain datatypes." Cooney said that this creates "confusion for users and excessive technical support" for Digital Bitcasting. Clooney cited both Microsoft's Windows Media Player and ActiveMovie technologies as offenders. Glaser said streaming media vendor Xing Technology Corp. planned to file evidence of similar problems with Microsoft's Media Player later Friday. Microsoft refuted these vendors assertions. "Navigator doesn't properly register itself with G2. It's a bug in RealNetworks' setup," said Gary Schare, Microsoft lead product manager, Windows Media Technologies. Schare said that the pre-beta "preview" release of G2 "worked fine" with Microsoft's Media Player. "This is all we had to test with," Schare said. RealNetworks didn't tell Microsoft about problems with the G2 beta, which it introduced last week, he said. The appropriate product groups at Microsoft and RealNetworks have exchanged information Friday regarding any ongoing G2 problems, Glaser and Schare both confirmed.