diff -ur cpl-5.3.1/configure cpl-5.3.1.fftw/configure
--- cpl-5.3.1/configure	2012-01-18 18:56:56.482524970 +0100
+++ cpl-5.3.1.fftw/configure	2012-01-18 19:01:45.098006700 +0100
@@ -12870,8 +12870,8 @@
 
     cpl_fftw_check_header="fftw3.h"
     cpl_fftwf_check_header="fftw3.h"
-    cpl_fftw_check_lib="libfftw3.a"
-    cpl_fftwf_check_lib="libfftw3f.a"
+    cpl_fftw_check_lib="libfftw3.so"
+    cpl_fftwf_check_lib="libfftw3f.so"
 
     cpl_fftw_includes=""
     cpl_fftwf_includes=""
@@ -12895,8 +12895,10 @@
         cpl_fftw_incdirs="$cpl_with_fftw_includes"
     fi
 
+    cpl_fftw_incdirs="$includedir"
     cpl_fftw_includes=no
 
+    cpl_fftw_libdirs="$libdir"
     for i in $cpl_fftw_incdirs; do
         for j in $cpl_fftw_check_header; do