Access to localized_str_tolower()

Howdy,

In my original implementation of citext, which I'm going to start
using for an app I'm developing, I pull in the wstring_lower function
from oracle_compat.c by simply declaring it at the top of citext.c,
just as if it were in an include file:

extern char * wstring_lower (char *str);

After I ported it to CVS HEAD, however, and discovered the
str_tolower() function in formatting.c, I wanted to try to make use of
it in 8.3, as well. But when I tried to include it in citext.c, it
simply didn't work. I put this at the top of citext.c:

extern char * localized_str_tolower(char *buff);

But when I try to use it, like so:

lcstr = localized_str_tolower(VARDATA_ANY(left));
rcstr = localized_str_tolower(VARDATA_ANY(right));

I get a compile-time error:

Undefined symbols:
"_localized_str_tolower", referenced from:
_citextcmp in citext.o
_citextcmp in citext.o
ld: symbol(s) not found
collect2: ld returned 1 exit status
make: *** [citext.so] Error 1

So, stupid C question, I'm sure: How can I use this function from my
module?

Oh, and on a side note, should I localized_str_tolower() or just
str_tolower()?

Thanks,

David