I already proposed adding Lua, but this is something we can't do at the moment. Code of the game is too convoluted to add something new without breaking other stuff.
As in my brainfuck interpreter. Also you can't use switch with strings and have to fill array manually with zeros. For example in C++ we can write "int array[5] = {0};" to fill with zeros, and in Java we don't have to do anything. In CBOT we can't even check if array field is initialized so we have to fill it manually before.
Really, strings need improvements in CBOT. They don't feel like they were objects at all, but at the same time they aren't arrays of chars either. It's weird.