Linker errors about ctype

I'm working with Agar on the PSP platform.  I have the library building 
successfully, but am running into a problem when I try to link the
Agar library with a simple test application.  I get a number of errors
similar to the following:

/usr/local/pspdev/lib/gcc/psp/4.1.0/../../../../psp/lib/libag_gui.a
  (keymap_ascii.o): In function `EmulateShiftUSKBD':
keymap_ascii.c:(.text+0x300): undefined reference to `__ctype_b_loc'
keymap_ascii.c:(.text+0x410): undefined reference to `__ctype_toupper_loc'

All of the errors relate to ctype - the other Agar symbols link OK.  Has 
anyone run into anything similar before?  The Agar library and the test 
app are being built with exactly the same toolchain and support 
libraries (clib, etc).

Thanks!

--Jason