Having been hampered for a while in my projects by a lack of a Pascal header for the newest version of Lua, I decided to make one. The project is currently on Sourceforge, and as far as I've tested supports both FPC 2.6+ and Delphi (version unknown).
An additional TLua class has been remodeled from the one created by Dennis D. Spreen to provide extra features and support Freepascal, and should help you get your projects quick Lua integration. The class and library bindings are fully useable on both Windows and Linux, 32 and 64 bit versions. I've already used it for quite some time on a Linux64, and made standard tests on Windows 32 and 64. I would love to have a few people test the bindings on various systems to see if there are unforeseen bugs crouching in the shadows .
If there is interest for it, I may also look into making compatible bindings for the Oxygene compilers.
The project page :