diff --git a/src/eval.c b/src/eval.c
index a1912fd..648d938 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -7930,7 +7930,7 @@
     {"sin",		1, 1, f_sin},
     {"sinh",		1, 1, f_sinh},
 #endif
-    {"sort",		1, 2, f_sort},
+    {"sort",		1, 3, f_sort},
     {"soundfold",	1, 1, f_soundfold},
     {"spellbadword",	0, 1, f_spellbadword},
     {"spellsuggest",	1, 3, f_spellsuggest},
@@ -16366,6 +16366,7 @@
 
 static int	item_compare_ic;
 static char_u	*item_compare_func;
+static dict_T	*item_compare_selfdict;
 static int	item_compare_func_err;
 #define ITEM_COMPARE_FAIL 999
 
@@ -16425,7 +16426,8 @@
 
     rettv.v_type = VAR_UNKNOWN;		/* clear_tv() uses this */
     res = call_func(item_compare_func, (int)STRLEN(item_compare_func),
-				 &rettv, 2, argv, 0L, 0L, &dummy, TRUE, NULL);
+				 &rettv, 2, argv, 0L, 0L, &dummy, TRUE,
+				 item_compare_selfdict);
     clear_tv(&argv[0]);
     clear_tv(&argv[1]);
 
@@ -16471,8 +16473,10 @@
 
 	item_compare_ic = FALSE;
 	item_compare_func = NULL;
+	item_compare_selfdict = NULL;
 	if (argvars[1].v_type != VAR_UNKNOWN)
 	{
+	    /* optional second argument: {func} */
 	    if (argvars[1].v_type == VAR_FUNC)
 		item_compare_func = argvars[1].vval.v_string;
 	    else
@@ -16487,6 +16491,17 @@
 		else
 		    item_compare_func = get_tv_string(&argvars[1]);
 	    }
+
+	    if (argvars[2].v_type != VAR_UNKNOWN)
+	    {
+		/* optional third argument: {dict} */
+		if (argvars[2].v_type != VAR_DICT)
+		{
+		    EMSG(_(e_dictreq));
+		    return;
+		}
+		item_compare_selfdict = argvars[2].vval.v_dict;
+	    }
 	}
 
 	/* Make an array with each entry pointing to an item in the List. */