OTH, I think the JEDI folks aren't the only ones who compared their ports to the Borland definitions. There are some definitions in the FPC API units that are "uncanningly" similar to the Borland ones, though the similarities may be a result of forced compatibility and not direct comparisons of the definitions.
Sometimes corrections in bugreports give an insight in Borland style, and that is then propogated to related code.
At this point, it may be appropriate to point out that in the great majority of civilized countries, specifications, which includes API definitions, are _not_ protected by copyright. To be crystal clear, looking at Borland's API definitions to ensure FPC's are compatible would not constitute a copyright violation.
It might be worth pointing out that while that is a legal right, actually defending against a cease and desist is more difficult. The problem is that copyright holders are somewhat bound to investigate copyright claims (if they have a habit of not, it can be used against them)
So what happens is they might commission some eager IP lawyer firm to investigate who, with minimal effort and maximal billing, might run some similarity software and produce "grounds for a cease and desist" without much nuance (like they come from the same MS headers).
Then your options are only to rip the disputed code out at tremendous (labour) cost (effectively do it anew, clean room), or put up your house to pay for a US legal defence. And as for the old nugget "just never go to the US", ask Julian Assange for his opinion.
(later: reworked long sentences a bit)