Either they don't exist or mention of them would be so obvious that the Firebird project would be able to incorporate the same improvements with little effort. The 'official' Open Source one. The 'official' certified one. Also available as an eval version for download, by purchase as a server kit, and all to be licenced by seat. The 'unofficial' one - Firebird.
Developers love open source.
Distributing the certified version with Borland tools completely misses the point, even if the source is supplied, because the 'open' source is different to the 'certified' source. Borland said so. Borland still don't look like they know what they want to do with InterBase and users are still suffering. These latest developments indicate that they are trying to resurrect the old InterBase business model. Having let the open source genie out of the bottle they are now desperately trying to shove it back in.