--- configure.py
+++ configure.py
@@ -941,8 +941,8 @@
                     # version.
                     link = "-framework Python"
                 elif ("--enable-shared" in ducfg.get("CONFIG_ARGS", "") and
-                      glob.glob("%s/lib/libpython%d.%d*" % (ducfg["exec_prefix"], py_major, py_minor))):
-                    lib_dir_flag = quote("-L%s/lib" % ducfg["exec_prefix"])
+                      glob.glob("%s/libpython%d.%d*" % (ducfg["LIBDIR"], py_major, py_minor))):
+                    lib_dir_flag = quote("-L%s" % ducfg["LIBDIR"])
                     link = "%s -lpython%d.%d%s" % (lib_dir_flag, py_major, py_minor, abi)
                 else:
                     sipconfig.inform("Qt Designer plugin disabled because Python library is static")