=== build/ac-macros/serf.m4
==================================================================
--- build/ac-macros/serf.m4	(revision 148316)
+++ build/ac-macros/serf.m4	(local)
@@ -15,9 +15,6 @@
     if test "$withval" = "yes" ; then
       AC_MSG_ERROR([--with-serf requires an argument.])
     else
-      if test "$svn_lib_neon" = "yes"; then
-        AC_MSG_ERROR([neon and serf can't be used at the same time.])
-      fi
       AC_MSG_NOTICE([serf library configuration])
       serf_prefix=$withval
       save_cppflags="$CPPFLAGS $SVN_APR_INCLUDES $SVN_APRUTIL_INCLUDES"
=== subversion/include/svn_config.h
==================================================================
--- subversion/include/svn_config.h	(revision 148316)
+++ subversion/include/svn_config.h	(local)
@@ -72,6 +72,7 @@
 #define SVN_CONFIG_OPTION_SSL_TRUST_DEFAULT_CA      "ssl-trust-default-ca"
 #define SVN_CONFIG_OPTION_SSL_CLIENT_CERT_FILE      "ssl-client-cert-file"
 #define SVN_CONFIG_OPTION_SSL_CLIENT_CERT_PASSWORD  "ssl-client-cert-password"
+#define SVN_CONFIG_OPTION_HTTP_LIBRARY              "http-library"
 
 #define SVN_CONFIG_CATEGORY_CONFIG          "config"
 #define SVN_CONFIG_SECTION_AUTH                 "auth"
=== subversion/libsvn_ra/ra_loader.c
==================================================================
--- subversion/libsvn_ra/ra_loader.c	(revision 148316)
+++ subversion/libsvn_ra/ra_loader.c	(local)
@@ -35,15 +35,21 @@
 #include "svn_xml.h"
 #include "svn_path.h"
 #include "svn_dso.h"
+#include "svn_config.h"
 #include "ra_loader.h"
 #include "svn_private_config.h"
 
 
-/* ### this file maps URL schemes to particular RA libraries. This is not
-   ### entirely correct, as a single scheme could potentially be served
-   ### by more than one loader. However, we can ignore that until we
-   ### actually run into a conflict within the scheme portion of a URL. */
+/* ### This file maps URL schemes to particular RA libraries.
+   ### Currently, the only pair of RA libraries which support the same
+   ### protocols are dav and serf.  svn_ra_open2 makes the assumption
+   ### that this is the case; that their 'schemes' fields are both
+   ### dav_schemes; and that "dav" is listed first. */
 
+#if defined(SVN_LIBSVN_CLIENT_LINKS_RA_DAV) && defined (SVN_LIBSVN_CLIENT_LINKS_RA_SERF)
+#define MUST_CHOOSE_DAV
+#endif
+
 
 /* These are the URI schemes that the respective libraries *may* support.
  * The schemes actually supported may be a subset of the schemes listed below.
@@ -369,7 +375,26 @@
   svn_ra_session_t *session;
   const struct ra_lib_defn *defn;
   const svn_ra__vtable_t *vtable = NULL;
+#ifdef MUST_CHOOSE_DAV
+  svn_config_t *servers = NULL;
+  const char *http_library = "dav";
 
+  if (config)
+    {
+      servers = apr_hash_get(config, SVN_CONFIG_CATEGORY_SERVERS,
+                             APR_HASH_KEY_STRING);
+      if (servers)
+        {
+          svn_config_get(servers, &http_library, SVN_CONFIG_SECTION_GLOBAL,
+                         SVN_CONFIG_OPTION_HTTP_LIBRARY, "dav");
+          if (strcmp(http_library, "dav") != 0 &&
+              strcmp(http_library, "serf") != 0)
+            return svn_error_create(SVN_ERR_RA_DAV_INVALID_CONFIG_VALUE, NULL,
+                                    _("Invalid config: unknown HTTP library"));
+        }
+    }
+#endif
+
   /* Find the library. */
   for (defn = ra_libraries; defn->ra_name != NULL; ++defn)
     {
@@ -379,6 +404,12 @@
         {
           svn_ra__init_func_t initfunc = defn->initfunc;
 
+#ifdef MUST_CHOOSE_DAV
+          if (defn->schemes == dav_schemes 
+              && strcmp(defn->ra_name, http_library) != 0)
+            continue;
+#endif
+
           if (! initfunc)
             SVN_ERR(load_ra_module(&initfunc, NULL, defn->ra_name,
                                    pool));
=== subversion/libsvn_subr/config_file.c
==================================================================
--- subversion/libsvn_subr/config_file.c	(revision 148316)
+++ subversion/libsvn_subr/config_file.c	(local)
@@ -792,6 +792,9 @@
         "###   ssl-client-cert-file       PKCS#12 format client certificate file"
                                                                              NL
         "###   ssl-client-cert-password   Client Key password, if needed."   NL
+        "###   http-library               Which library to use for http/https"
+                                                                             NL
+        "###                              connections (dav or serf)"         NL
         "###"                                                                NL
         "### HTTP timeouts, if given, are specified in seconds.  A timeout"  NL
         "### of 0, i.e. zero, causes a builtin default to be used."          NL