REPLACE Doesn't.

[toml_12953]

I'm trying to replace spaces in a string with zeroes but I get the same string back unchanged. The program below prints
" 9"
" 9"
Of course I'm doing something wrong but I can't figure out what. REPLACE does work at the home screen.

Tom L

PHP Code:

EXPORT test()
BEGIN
  local x,i;
  print();
  x:="    9";
  print(""""+x+"""");
  for i from 1 to 4 do
   replace(x,i,"0");
  end;
  print(""""+x+""""); 
END;