Checking if your kit is complete...
Looks good
Note (probably harmless): No library found for -lgsl
Note (probably harmless): No library found for -lgslcblas
Writing Makefile for Math::GSL
cp GSL.pm blib/lib/Math/GSL.pm
/Users/cpanrun/build/5.10.0/bin/perl /Users/cpanrun/build/5.10.0/lib/ExtUtils/xsubpp  -typemap /Users/cpanrun/build/5.10.0/lib/ExtUtils/typemap  GSL.xs > GSL.xsc && mv GSL.xsc GSL.c
gcc -c   -fno-common -DPERL_DARWIN -no-cpp-precomp -arch ppc -arch i386 -nostdinc -B/Developer/SDKs/MacOSX10.4u.sdk/usr/include/gcc -B/Developer/SDKs/MacOSX10.4u.sdk/usr/lib/gcc -isystem/Developer/SDKs/MacOSX10.4u.sdk/usr/include -F/Developer/SDKs/MacOSX10.4u.sdk/System/Library/Frameworks -mmacosx-version-min=10.3 -DPRIVLIB_LAST_IN_INC -fno-strict-aliasing -pipe -O3   -DVERSION=\"0.01\" -DXS_VERSION=\"0.01\"  "-I/Users/cpanrun/build/5.10.0/lib/CORE"   GSL.c
GSL.xs:4:27: error: gsl/gsl_errno.h: No such file or directory
GSL.xs:5:26: error: gsl/gsl_poly.h: No such file or directory
GSL.xs: In function 'XS_Math__GSL_poly_complex_solve':
GSL.xs:31: error: 'gsl_poly_complex_workspace' undeclared (first use in this function)
GSL.xs:31: error: (Each undeclared identifier is reported only once
GSL.xs:31: error: for each function it appears in.)
GSL.xs:31: error: 'w' undeclared (first use in this function)
GSL.xs:36: error: 'GSL_SUCCESS' undeclared (first use in this function)
GSL.xs:4:27: error: gsl/gsl_errno.h: No such file or directory
GSL.xs:5:26: error: gsl/gsl_poly.h: No such file or directory
GSL.xs: In function 'XS_Math__GSL_poly_complex_solve':
GSL.xs:31: error: 'gsl_poly_complex_workspace' undeclared (first use in this function)
GSL.xs:31: error: (Each undeclared identifier is reported only once
GSL.xs:31: error: for each function it appears in.)
GSL.xs:31: error: 'w' undeclared (first use in this function)
GSL.xs:36: error: 'GSL_SUCCESS' undeclared (first use in this function)
lipo: can't open input file: /var/tmp//ccMMotK2.out (No such file or directory)
make: *** [GSL.o] Error 1