Compiling TLA on BeOS
These tips are for TLA 1.2.2rc2 on BeOS R5 MAX + BONE (though I doubt BONE is of relevance).
Requirements
Here is a slight list of what I needed to get
GNU diffutils, version >= 2.8 (tla requires gnu diff/patch). Version 2.8.1. compiles without problems.
Gnu Patch 2.5.4. Whatever I did, the test always failed, until I found it and commented it out -- I've yet to see tla work though.
All issues resolved, if not crudely, patch might appear here soon 
make test
You'll need an external which command for make test to succeed.