Index: main.c
===================================================================
--- main.c	(revision 17054)
+++ main.c	(working copy)
@@ -69,7 +69,7 @@ const apr_getopt_option_t svn_cl__option
     {"quiet",         'q', 0, N_("print as little as possible")},
     {"recursive",     'R', 0, N_("descend recursively")},
     {"non-recursive", 'N', 0, N_("operate on single directory only")},
-    {"change",        'c', 1, N_("Shorthand for the revision range NUMBER-1:NUMBER")},
+    {"change",        'c', 1, N_("the change made by revision ARG (like -r ARG-1:ARG)")},
     {"revision",      'r', 1, N_
      ("ARG (some commands also take ARG1:ARG2 range)\n"
       "                             A revision argument can be one of:\n"
@@ -934,7 +934,7 @@ main (int argc, const char * const *argv
           if (end == opt_arg || *end != '\0')
             {
               err = svn_error_create (SVN_ERR_CL_ARG_PARSING_ERROR, NULL,
-                                      _("Non-numeric change argument given"));
+                                      _("Non-numeric change argument given to -c"));
               return svn_cmdline_handle_exit_error (err, pool, "svn: ");
             }
           else if (opt_state.end_revision.value.number == 0)
@@ -943,6 +943,12 @@ main (int argc, const char * const *argv
                                       _("There is no change 0"));
               return svn_cmdline_handle_exit_error (err, pool, "svn: ");
             }
+          else if (opt_state.end_revision.value.number < 0)
+            {
+              err = svn_error_create (SVN_ERR_CL_ARG_PARSING_ERROR, NULL,
+                                      _("Argument to -c must be positive"));
+              return svn_cmdline_handle_exit_error (err, pool, "svn: ");
+            }
           opt_state.start_revision.value.number = opt_state.end_revision.value.number - 1;
           opt_state.start_revision.kind = svn_opt_revision_number;      
         }
@@ -953,7 +959,7 @@ main (int argc, const char * const *argv
             err = svn_error_create
               (SVN_ERR_CL_ARG_PARSING_ERROR, NULL,
                _("Multiple revision arguments encountered; "
-                 "can't specifiy -r and -c, or"
+                 "can't specify -r and -c, or "
                  "try '-r M:N' instead of '-r M -r N'"));
             return svn_cmdline_handle_exit_error (err, pool, "svn: ");
           }