Problem to install rtiff package from source

I would like to install the rtiff package, which does not exist as  
binary. I have MacPorts installed and tried with
sudo R CMD INSTALL --configure-vars='LDFLAGS=-L/opt/local/lib  
CPPFLAGS=-I/opt/local/include' rtiff_1.4.tar.gz
(which worked for rimage installation from source)

The result is
* Installing to library ?/Library/Frameworks/R.framework/Resources/ 
library?
* Installing *source* package ?rtiff? ...
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 TIFFOpen in -ltiff... yes
configure: creating ./config.status
config.status: creating src/Makevars
** libs
** arch - i386
gcc -arch i386 -std=gnu99 -I/Library/Frameworks/R.framework/Resources/ 
include -I/Library/Frameworks/R.framework/Resources/include/i386  -I/ 
usr/local/include    -fPIC  -g -O2 -c rtiff.c -o rtiff.o
rtiff.c: In function ?getTiffDescription?:
rtiff.c:136: warning: ?return? with no value, in function returning  
non-void
gcc -arch i386 -std=gnu99 -dynamiclib -Wl,-headerpad_max_install_names  
-mmacosx-version-min=10.4 -undefined dynamic_lookup -single_module - 
multiply_defined suppress -L/usr/local/lib -o rtiff.so rtiff.o -ltiff - 
F/Library/Frameworks/R.framework/.. -framework R -Wl,-framework - 
Wl,CoreFoundation
ld: library not found for -ltiff
collect2: ld returned 1 exit status
make: *** [rtiff.so] Error 1
Fehler: compilation failed f?r Paket ?rtiff?
* Removing ?/Library/Frameworks/R.framework/Resources/library/rtiff?

Seemingly the LDFLAGS are not sent to gcc?

Any help is appreciated
Regards
Karsten
karo03de at gmail.com