configure oddity when run via MacPorts

[Jeremy Huddleston]

I'm trying to update cdparanoia.  I can build it manually, but it  
fails configure via port (I updated base yesterday):

...
--->  Configuring cdparanoia
checking build system type... powerpc-apple-darwin9.7.0
checking host system type... powerpc-apple-darwin9.7.0
checking for ranlib... ranlib
checking for ar... ar
checking for install... /usr/bin/install -c
checking how to run the C preprocessor... /usr/bin/cpp-4.0
checking for egrep... grep -E
checking for ANSI C header files... no
checking for sys/types.h... no
checking for sys/stat.h... no
checking for stdlib.h... no
checking for string.h... no
checking for memory.h... no
checking for strings.h... no
checking for inttypes.h... no
checking for stdint.h... no
checking for unistd.h... no
checking for short... no
checking size of short... 0
checking for int... no
checking size of int... 0
checking for long... no
checking size of long... 0
checking for long long... no
checking size of long long... 0
checking for int16_t... no
checking for int32_t... no
configure: error: No 16 bit type found on this platform!
Error: Target org.macports.configure returned: configure failure:  
shell command " cd "/opt/local/var/macports/build/ 
_Volumes_MyBook_src_macports-trunk_dports_audio_cdparanoia/work/ 
cdparanoia-III-10.2" && ./configure --prefix=/opt/local " returned  
error 1
Command output: checking build system type... powerpc-apple-darwin9.7.0
...

but it works fine manually:

/opt/local/var/macports/build/_Volumes_MyBook_src_macports- 
trunk_dports_audio_cdparanoia/work/cdparanoia-III-10.2 $ sudo ./ 
configure --prefix=/opt/local
checking build system type... powerpc-apple-darwin9.7.0
checking host system type... powerpc-apple-darwin9.7.0
checking for gcc... gcc
checking for C compiler default output file name... a.out
checking whether the C compiler works... yes
checking whether we are cross compiling... no
checking for suffix of executables...
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether gcc accepts -g... yes
checking for gcc option to accept ANSI C... none needed
checking for ranlib... ranlib
checking for ar... ar
checking for install... install
checking how to run the C preprocessor... gcc -E
checking for egrep... grep -E
checking for ANSI C header files... yes
checking for sys/types.h... yes
checking for sys/stat.h... yes
checking for stdlib.h... yes
...

----

here's a snippit from config.log for the missing stdlib.h:

configure:2936: test -s conftest.
configure:2939: $? = 1

----

compared to when I do it manually:

configure:2936: test -s conftest.o
configure:2939: $? = 0


----

The configure script is skipping all these tests when run through  
MacPorts:

checking for gcc... gcc
checking for C compiler default output file name... a.out
checking whether the C compiler works... yes
checking whether we are cross compiling... no
checking for suffix of executables...
checking for suffix of object files... o
checking whether we are using the GNU C compiler... yes
checking whether gcc accepts -g... yes
checking for gcc option to accept ANSI C... none needed

so it doesn't know about the ".o" suffix.

Does anyone have a clue why this is happening?