Trouble linking libraries when building a C MEX file in Xcode

I am trying to build a MATLAB MEX file in Xcode (version 4.6.3) for debugging purposes. I was already able to successfully compile the program in MATLAB (R2013a) using this command:

>> mex src/main.c src/binomial.c src/gaussian1.c src/gaussianU.c src/poisson.c -Iinclude -I/usr/local/include -L/usr/local/lib -lmpfr -output cpdetect_c

When I try to build it in Xcode, the program compiles successfully, but the build fails at the linking stage with errors like this:

Undefined symbols for architecture x86_64:
  "_mexErrMsgIdAndTxt", referenced from:
      _mexFunction in main.o
  "_mexPrintf", referenced from:
      _find_gaussian1_change_point in gaussian1.o
      _cpdetect in main.o
      _find_poisson_change_point in poisson.o
  "_mpfr_add", referenced from:
      _find_gaussian1_change_point in gaussian1.o
      _find_gaussianU_change_point in gaussianU.o
      _find_poisson_change_point in poisson.o
  "_mxCreateDoubleMatrix_730", referenced from:
      _mexFunction in main.o

As described in this post, I have the following settings in Xcode:

>> Other Linker Flags: -lmx -lmex -lmat -lmpfr
>> Header Search Paths: $(MATLABROOT)/extern/include  
   /Users/myName/Documents/MATLAB/SingleMolecule/Current_Version/cpdetect_c_mex/include 
   /usr/local/include
>> Library Search Paths: $(MATLABROOT)/bin/maci64 /usr/local/lib

but this is apparently not sufficient for successful linking. What am I missing? Thanks for any suggestions!

[Kaustubha Govind]

I wonder if you are building a 64-bit MEX in Xcode against 32-bit MATLAB libraries, or vice versa.