diff --git a/src/testdir/test_vim9_func.vim b/src/testdir/test_vim9_func.vim
index 73ff693..cdaba5a 100644
--- a/src/testdir/test_vim9_func.vim
+++ b/src/testdir/test_vim9_func.vim
@@ -781,6 +781,16 @@
       Func(1, 'a')
   END
   CheckScriptFailure(lines, 'E1013: Argument 1: type mismatch')
+
+  lines =<< trim END
+      vim9script
+      def Func(  # some comment
+                ...l = []
+                )
+        echo l
+      enddef
+  END
+  CheckScriptFailure(lines, 'E1160:')
 enddef
 
 let s:value = ''
diff --git a/src/userfunc.c b/src/userfunc.c
index e220781..82df0bb 100644
--- a/src/userfunc.c
+++ b/src/userfunc.c
@@ -241,6 +241,11 @@
 									 skip);
 		if (p == arg)
 		    break;
+		if (*skipwhite(p) == '=')
+		{
+		    emsg(_(e_cannot_use_default_for_variable_arguments));
+		    break;
+		}
 	    }
 	}
 	else
diff --git a/src/version.c b/src/version.c
index 871e048..c6f44a4 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2481,
+/**/
     2480,
 /**/
     2479,