I think it's a case of dodgy sentence construction.
The software packages, including 400,000 units of Microsoft's new Office XP program, are valued at $900 million by the company, although others peg their price tag even higher.
The total of the software packages is valued at $900 M by MS. Not just the OXP licenses.
This type of sentence construction seems to be popular in the press for some reason...
Cheers,
Scott.