https://issues.apache.org/jira/browse/AMQCPP-567

wherget patch updates sed command in apr_tools.m4 to account for issues
on Mac.
diff --git a/activemq-cpp/m4/apr_tools.m4 b/activemq-cpp/m4/apr_tools.m4
index 76c18c9..56dee7d 100644
--- a/activemq-cpp/m4/apr_tools.m4
+++ b/activemq-cpp/m4/apr_tools.m4
@@ -80,7 +80,7 @@
     AC_MSG_ERROR([apr-config --link-libtool --libs failed])
   fi
 
-  APR_PKGCONFIG="`echo $apr_config | sed 's,\(.*/\)\?apr\(-\?.*\)-config$,apr\2,'`"
+  APR_PKGCONFIG="`echo $apr_config | sed 's/\(.*\/\)\{0,1\}apr\(-\{0,1\}.*\)-config$/apr\2/'`"
 
   AC_SUBST([APR_LIBS])
   AC_SUBST([APR_LDFLAGS])