luac -s produced bad code (Lua 5.0)

[rubanetz <rubanetz@...>]

Good Day,  
  Recently I tried to replace plain text lua files with results of luac -s for demo version and got many "error loading package `xxx' (bad code in ./xxx.lua)"
  If anyone encountered such problems, please write your suggestions. 
  Just to stop bashing for not changing version - its old code and there is no money to rewrite it. I know that staying with old code is not a good thing but the software started in 2003 so it sticks with Lua 5.0. 
Best regards, Miroslav Rubanets