Index: generic/nsf.c
===================================================================
diff -u -N -rf69d53266ed98cdac54bd60985a26d1694238234 -r5a31aba4393fd948e89acf72dfca9c40e8b93334
--- generic/nsf.c	(.../nsf.c)	(revision f69d53266ed98cdac54bd60985a26d1694238234)
+++ generic/nsf.c	(.../nsf.c)	(revision 5a31aba4393fd948e89acf72dfca9c40e8b93334)
@@ -24320,7 +24320,7 @@
 
         INCR_REF_COUNT2("methodPathObj", methodPathObj);
 
-        NsfPrintError(interp, "required argument '%s' is missing, should be:\n\t%s%s%s %s",
+        NsfPrintError(interp, "required argument '%s' is missing, should be:\n        %s%s%s %s",
                       (pPtr->nameObj != NULL) ? ObjStr(pPtr->nameObj) : pPtr->name,
                       (pcPtr->object != NULL) ? ObjectName(pcPtr->object) : "", (pcPtr->object != NULL) ? " " : "",
                       ObjStr(methodPathObj),
@@ -31781,7 +31781,7 @@
       if (unlikely(varObj == NULL)) {
         Tcl_Obj *paramDefsObj = NsfParamDefsSyntax(interp, paramDefs->paramsPtr, object, NULL);
 
-        NsfPrintError(interp, "required argument '%s' is missing, should be:\n\t%s%s%s %s", (paramPtr->nameObj != NULL) ? ObjStr(paramPtr->nameObj) : paramPtr->name, (pc.object != NULL) ? ObjectName(pc.object) : "", (pc.object != NULL) ? " " : "",
+        NsfPrintError(interp, "required argument '%s' is missing, should be:\n        %s%s%s %s", (paramPtr->nameObj != NULL) ? ObjStr(paramPtr->nameObj) : paramPtr->name, (pc.object != NULL) ? ObjectName(pc.object) : "", (pc.object != NULL) ? " " : "",
                       ObjStr(pc.full_objv[0]),
                       ObjStr(paramDefsObj));
         DECR_REF_COUNT2("paramDefsObj", paramDefsObj);
Index: library/xotcl/tests/testx.xotcl
===================================================================
diff -u -N -r992c44194bc02e57151a037ebda546c287af4d03 -r5a31aba4393fd948e89acf72dfca9c40e8b93334
--- library/xotcl/tests/testx.xotcl	(.../testx.xotcl)	(revision 992c44194bc02e57151a037ebda546c287af4d03)
+++ library/xotcl/tests/testx.xotcl	(.../testx.xotcl)	(revision 5a31aba4393fd948e89acf72dfca9c40e8b93334)
@@ -4039,19 +4039,19 @@
     o y
   } m
   errorCheck $m {required argument 'a' is missing, should be:
-	::o y ?-x /value/? ?-a /value/? /a/ /b/} "wrong \# check 2"
+        ::o y ?-x /value/? ?-a /value/? /a/ /b/} "wrong \# check 2"
 
   catch {
     o y -x 1
   } m
   errorCheck $m {required argument 'a' is missing, should be:
-	::o y ?-x /value/? ?-a /value/? /a/ /b/} "wrong \# check 3"
+        ::o y ?-x /value/? ?-a /value/? /a/ /b/} "wrong \# check 3"
 
   catch {
     o z1 a 1 2 3
   } m
   errorCheck $m {required argument 'x' is missing, should be:
-	::o z1 -x /value/ ?-a /value/? /a/ ?/arg .../?} "required missing"
+        ::o z1 -x /value/ ?-a /value/? /a/ ?/arg .../?} "required missing"
   errorCheck [o z1 -x 1  a 1 2 3] "1 -- 1 2 3" "invocation 1"
   errorCheck [o z2 -x 2  a 1 2 3] "2 -- a 1 2 3 -- 1  -- 1 2" "invocation 2"
   catch {
@@ -4131,7 +4131,7 @@
   catch {oa foo "--"} msg
   
   errorCheck $msg {required argument 'b' is missing, should be:
-	::oa foo ?-a /value/? /b/} "Non-pos arg: double dash alone"
+        ::oa foo ?-a /value/? /b/} "Non-pos arg: double dash alone"
 	
   Class C
   C create c1