Microsoft lawyers locked horns with government witness Edward Felten, the Princeton professor who last year testified that Internet Explorer (IE) could be unbundled from the Windows operating system.
Felten is one of three witnesses who have been called by the US government to strengthen its case against Microsoft, as the anti-trust case inches towards a conclusion.
Microsoft lawyer Steven Holley sought to cast doubt on the essence of Felten's testimony - that there is no technical reason for Microsoft to bundle IE into Windows - by making him repeat a demonstration of his unbundling program that Felten claimed, in court last December, could remove IE from Windows.
However, after the repeat performance was unsuccessful, Felten argued that his program was a prototype and could have been affected by other software running on the trial machine.
Microsoft claims the operating system and browser are so closely integrated that IE could not be removed without crippling Windows.
Felten's testimony followed evidence from senior IBM executive Garry Norris, who earlier in the week outlined the 'carrot and stick' tactics which he claimed Microsoft used to convince IBM to promote Windows 95 exclusively.
While Microsoft lawyers argued that it did not specifically demand IBM abandon its own OS/2 product, Norris argued that the conditions of the licensing agreement Microsoft offered IBM for Windows 95 amounted to the same thing.
Vendor giant fires love arrow at New Signature and SAP partner Edenhouse
CEO Klaus Schlichtherle says 'sizeable' deal close to being inked as distributor chases €1bn turnover
Deloitte has been appointed as administrator for the struggling distie
It's been announced that billionaire tech pioneer Paul Allen died on Monday from non-Hodgkin lymphoma