By only supporting binary versions that they have supplied to enterprise customers, [open source enterprise vendors] have taken away the advantages of open source from the customer. What open source does for [the vendor] is give them a cheaper way of developing their software by allowing people to take the community code and enhance it, and they get the benefits of those enhancements. [...] An enterprise has to be prepared to ensure that the enterprise open source vendor they are dealing with is really as open as they need.
He closes with a checklist which helps to receive all advantages and freedom open source software.
If in any problem you find yourself doing an immense amount of work, the answer can be obtained by simple inspection.