$ cat enable-thread-safe-client-configure.patch
Index: configure
===================================================================
--- configure   (revision 1932)
+++ configure   (working copy)
@@ -18952,13 +18952,13 @@
 fi


-echo "$as_me:$LINENO: checking for mysql_init in -lmysqlclient" >&5
-echo $ECHO_N "checking for mysql_init in -lmysqlclient... $ECHO_C" >&6
+echo "$as_me:$LINENO: checking for mysql_init in -lmysqlclient_r" >&5
+echo $ECHO_N "checking for mysql_init in -lmysqlclient_r... $ECHO_C" >&6
 if test "${ac_cv_lib_mysqlclient_mysql_init+set}" = set; then
   echo $ECHO_N "(cached) $ECHO_C" >&6
 else
   ac_check_lib_save_LIBS=$LIBS
-LIBS="-lmysqlclient  $LIBS"
+LIBS="-lmysqlclient_r  $LIBS"
 cat >conftest.$ac_ext <<_ACEOF
 /* confdefs.h.  */
 _ACEOF
@@ -19020,7 +19020,7 @@
 #define HAVE_LIBMYSQLCLIENT 1
 _ACEOF

-  LIBS="-lmysqlclient $LIBS"
+  LIBS="-lmysqlclient_r $LIBS"

 else

Index: configure.ac
===================================================================
--- configure.ac        (revision 1932)
+++ configure.ac        (working copy)
@@ -124,7 +124,7 @@
     ])
 AC_CHECK_LIB( z, compress, [],[AC_MSG_ERROR([Missing zlib])] )
 AC_CHECK_LIB( compat, ftime )
-AC_CHECK_LIB( mysqlclient, mysql_init, [],[AC_CHECK_LIB(mysql, mysql_init,[],[AC_MSG_ERROR([Missing mysql])])])
+AC_CHECK_LIB( mysqlclient_r, mysql_init, [],[AC_CHECK_LIB(mysql, mysql_init,[],[AC_MSG_ERROR([Missing mysql])])])
 AC_CHECK_LIB( ssl, SHA1_Init, [], [AC_CHECK_LIB(ssl, SHA1_Init,[],[AC_MSG_ERROR([Missing openssl])])])

 CPPFLAGS_SAVE=$CPPFLAGS