[plt-scheme] "make both" failing for 4.2.5 on linux when --enable-shared

FYI, when building 4.2.5 on Linux x86 32-bit, "make both" fails for me 
when I have "--enable-both --enable-shared".

For now, I will stop using "--enable-shared", since the CGC is crucial 
to me.


make both
[[...]]
make foreign-stuff
make[4]: Entering directory `/usr/local/src/plt-4.2.5/src/mzscheme'
cd ../foreign; make all
make[5]: Entering directory `/usr/local/src/plt-4.2.5/src/foreign'
make foreign.lo
make[6]: Entering directory `/usr/local/src/plt-4.2.5/src/foreign'
/usr/local/src/plt-4.2.5/src/lt/libtool --mode=compile --tag=CC gcc -g 
-O2  -Wall  -pthread    -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 
-DMZ_USES_SHARED_LIB -I./../mzscheme -I./../mzscheme/include 
-I./../mzscheme/src -Igcc/libffi/include -c ./foreign.c -o foreign.lo
mkdir .libs
 gcc -g -O2 -Wall -pthread -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 
-DMZ_USES_SHARED_LIB -I./../mzscheme -I./../mzscheme/include 
-I./../mzscheme/src -Igcc/libffi/include -c ./foreign.c  -fPIC -DPIC -o 
.libs/foreign.o
In file included from ./../mzscheme/include/scheme.h:1098,
                 from ./../mzscheme/src/schpriv.h:21,
                 from ./foreign.c:9:
./../mzscheme/include/schthread.h:321:6: error: #error 
scheme_get_thread_local_variables no defined on this platform
make[6]: *** [foreign.lo] Error 1
make[6]: Leaving directory `/usr/local/src/plt-4.2.5/src/foreign'
make[5]: *** [all] Error 2
make[5]: Leaving directory `/usr/local/src/plt-4.2.5/src/foreign'
make[4]: *** [foreign-stuff] Error 2
make[4]: Leaving directory `/usr/local/src/plt-4.2.5/src/mzscheme'
make[3]: *** [common] Error 2
make[3]: Leaving directory `/usr/local/src/plt-4.2.5/src/mzscheme'
make[2]: *** [cgc] Error 2
make[2]: Leaving directory `/usr/local/src/plt-4.2.5/src/mzscheme'
make[1]: *** [cgc] Error 2
make[1]: Leaving directory `/usr/local/src/plt-4.2.5/src'
make: *** [both] Error 2