diff --git a/lib/cnode.c b/lib/cnode.c
index 6d65154..a487075 100644
--- a/lib/cnode.c
+++ b/lib/cnode.c
@@ -107,9 +107,12 @@ hcl_cnode_t* hcl_makecnodesymbol (hcl_t* hcl, int flags, const hcl_loc_t* loc, c
 	return c;
 }
 
-hcl_cnode_t* hcl_makecnodedsymbol (hcl_t* hcl, int flags, const hcl_loc_t* loc, const hcl_oocs_t* tok)
+hcl_cnode_t* hcl_makecnodedsymbol (hcl_t* hcl, int flags, const hcl_loc_t* loc, const hcl_oocs_t* tok, int is_cla)
 {
-	return make_cnode(hcl, HCL_CNODE_DSYMBOL, flags, loc, tok);
+	hcl_cnode_t* c = make_cnode(hcl, HCL_CNODE_DSYMBOL, flags, loc, tok);
+	if (HCL_UNLIKELY(!c)) return HCL_NULL;
+	c->u.dsymbol.is_cla = is_cla;
+	return c;
 }
 
 hcl_cnode_t* hcl_makecnodestrlit (hcl_t* hcl, int flags, const hcl_loc_t* loc, const hcl_oocs_t* tok)
diff --git a/lib/comp.c b/lib/comp.c
index 08dcaa4..1a2df3f 100644
--- a/lib/comp.c
+++ b/lib/comp.c
@@ -400,9 +400,24 @@ HCL_INFO2 (hcl, "CLASS NAMED VAR [%.*js]\n", name->len, name->ptr);
 	return 0; /* not found */
 }
 
-static int find_variable_backward_with_token (hcl_t* hcl, const hcl_cnode_t* token, hcl_var_info_t* vi)
+static int find_variable_backward_with_token (hcl_t* hcl, const hcl_cnode_t* cnode, hcl_var_info_t* vi)
 {
-	return find_variable_backward_with_word(hcl, HCL_CNODE_GET_TOK(token), HCL_CNODE_GET_LOC(token), 0, vi);
+	if (HCL_CNODE_IS_DSYMBOL_CLA(cnode))
+	{
+		/* prefixed with self or super. remove the first segment */
+		hcl_oocs_t newtok;
+		newtok = *HCL_CNODE_GET_TOK(cnode);
+		while (*newtok.ptr != '.')
+		{
+			newtok.ptr++;
+			newtok.len--;
+		}
+		newtok.ptr++;
+		newtok.len--;
+		return find_variable_backward_with_word(hcl, &newtok, HCL_CNODE_GET_LOC(cnode), 1, vi);
+	}
+
+	return find_variable_backward_with_word(hcl, HCL_CNODE_GET_TOK(cnode), HCL_CNODE_GET_LOC(cnode), HCL_CNODE_IS_DSYMBOL_CLA(cnode), vi);
 }
 
 /* ========================================================================= */
@@ -987,7 +1002,7 @@ static void pop_cblk (hcl_t* hcl)
 	hcl->c->cblk.depth--;
 }
 
-static int push_clsblk (hcl_t* hcl, const hcl_loc_t* errloc, hcl_oow_t nivars, hcl_oow_t ncvars, const hcl_ooch_t*  ivars_str, hcl_oow_t ivars_strlen, const hcl_ooch_t* cvars_str, hcl_oow_t cvars_strlen)
+static int push_clsblk (hcl_t* hcl, const hcl_loc_t* errloc, hcl_oow_t nivars, hcl_oow_t ncvars, const hcl_ooch_t* ivars_str, hcl_oow_t ivars_strlen, const hcl_ooch_t* cvars_str, hcl_oow_t cvars_strlen)
 {
 	hcl_oow_t new_depth;
 	hcl_clsblk_info_t* ci;
@@ -1353,7 +1368,7 @@ static int collect_vardcl (hcl_t* hcl, hcl_cnode_t* obj, hcl_cnode_t** nextobj,
 	#if 0
 		if (!HCL_CNODE_IS_SYMBOL(var))
 		{
-			hcl_setsynerrbfmt (hcl, HCL_SYNERR_ARGNAME, HCL_CNODE_GET_LOC(var), HCL_CNODE_GET_TOK(var), "local variable not a symbol");
+			hcl_setsynerrbfmt (hcl, HCL_SYNERR_ARGNAME, HCL_CNODE_GET_LOC(var), HCL_CNODE_GET_TOK(var), "local variable not symbol");
 			return -1;
 		}
 
@@ -2343,11 +2358,21 @@ static int compile_class (hcl_t* hcl, hcl_cnode_t* src)
 		/* defclass followed by a class name */
 		if (HCL_CNODE_SYMBOL_SYNCODE(class_name)) /*|| HCL_OBJ_GET_FLAGS_KERNEL(class_name) >= 1) */
 		{
-			hcl_setsynerrbfmt (hcl, HCL_SYNERR_BANNEDVARNAME, HCL_CNODE_GET_LOC(class_name), HCL_CNODE_GET_TOK(class_name), "special symbol not to be used as a class name");
+			hcl_setsynerrbfmt (hcl, HCL_SYNERR_BANNEDVARNAME, HCL_CNODE_GET_LOC(class_name), HCL_CNODE_GET_TOK(class_name), "special symbol not to be used as class name");
 			return -1;
 		}
 		obj = HCL_CNODE_CONS_CDR(obj);
 	}
+	else if (HCL_CNODE_IS_DSYMBOL(class_name))
+	{
+		if (!HCL_CNODE_IS_DSYMBOL_CLA(class_name))
+		{
+			hcl_setsynerrbfmt (hcl, HCL_SYNERR_BANNEDVARNAME, HCL_CNODE_GET_LOC(class_name), HCL_CNODE_GET_TOK(class_name), "dottted symbol not to be used as class name");
+			return -1;
+		}
+
+		obj = HCL_CNODE_CONS_CDR(obj);
+	}
 
 	if (obj)
 	{
@@ -2636,7 +2661,6 @@ static HCL_INLINE int compile_class_p2 (hcl_t* hcl)
 	}
 	else
 	{
-		//POP_CFRAME (hcl);
 		SWITCH_TOP_CFRAME (hcl, COP_COMPILE_CLASS_P3, cf->operand);
 #endif
 	}
@@ -2702,7 +2726,7 @@ static int compile_lambda (hcl_t* hcl, hcl_cnode_t* src, int defun)
 
 		if (!HCL_CNODE_IS_SYMBOL(defun_name))
 		{
-			hcl_setsynerrbfmt (hcl, HCL_SYNERR_VARNAME, HCL_CNODE_GET_LOC(defun_name), HCL_CNODE_GET_TOK(defun_name), "name not a symbol in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+			hcl_setsynerrbfmt (hcl, HCL_SYNERR_VARNAME, HCL_CNODE_GET_LOC(defun_name), HCL_CNODE_GET_TOK(defun_name), "name not symbol in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 			return -1;
 		}
 
@@ -2761,7 +2785,7 @@ static int compile_lambda (hcl_t* hcl, hcl_cnode_t* src, int defun)
 			{
 				if (!HCL_CNODE_IS_SYMBOL(arg))
 				{
-					hcl_setsynerrbfmt (hcl, HCL_SYNERR_VARNAME, HCL_CNODE_GET_LOC(arg), HCL_CNODE_GET_TOK(arg), "return variable not a symbol in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+					hcl_setsynerrbfmt (hcl, HCL_SYNERR_VARNAME, HCL_CNODE_GET_LOC(arg), HCL_CNODE_GET_TOK(arg), "return variable not symbol in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 					return -1;
 				}
 
@@ -2805,7 +2829,7 @@ static int compile_lambda (hcl_t* hcl, hcl_cnode_t* src, int defun)
 				}
 				else if (!HCL_CNODE_IS_SYMBOL(arg))
 				{
-					hcl_setsynerrbfmt (hcl, HCL_SYNERR_ARGNAME, HCL_CNODE_GET_LOC(arg), HCL_CNODE_GET_TOK(arg), "argument not a symbol in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+					hcl_setsynerrbfmt (hcl, HCL_SYNERR_ARGNAME, HCL_CNODE_GET_LOC(arg), HCL_CNODE_GET_TOK(arg), "argument not symbol in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 					return -1;
 				}
 				else
@@ -3045,13 +3069,13 @@ static int compile_set (hcl_t* hcl, hcl_cnode_t* src)
 	}
 
 	var = HCL_CNODE_CONS_CAR(obj);
-	if (!HCL_CNODE_IS_SYMBOL(var))
+	if (!HCL_CNODE_IS_SYMBOL(var) && !HCL_CNODE_IS_DSYMBOL_CLA(var))
 	{
-		hcl_setsynerrbfmt (hcl, HCL_SYNERR_VARNAME, HCL_CNODE_GET_LOC(var), HCL_CNODE_GET_TOK(var), "variable name not a symbol in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+		hcl_setsynerrbfmt (hcl, HCL_SYNERR_VARNAME, HCL_CNODE_GET_LOC(var), HCL_CNODE_GET_TOK(var), "variable name not symbol in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 		return -1;
 	}
 
-	if (HCL_CNODE_SYMBOL_SYNCODE(var)/* || HCL_OBJ_GET_FLAGS_KERNEL(var) >= 2*/)
+	if (HCL_CNODE_IS_SYMBOL(var) && HCL_CNODE_SYMBOL_SYNCODE(var)/* || HCL_OBJ_GET_FLAGS_KERNEL(var) >= 2*/)
 	{
 		hcl_setsynerrbfmt (hcl, HCL_SYNERR_BANNEDVARNAME, HCL_CNODE_GET_LOC(var), HCL_CNODE_GET_TOK(var), "special symbol not to be used as a variable name in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 		return -1;
@@ -3085,6 +3109,13 @@ static int compile_set (hcl_t* hcl, hcl_cnode_t* src)
 
 	if (x == 0)
 	{
+		if (HCL_CNODE_IS_DSYMBOL_CLA(var))
+		{
+			hcl_setsynerrbfmt (hcl, HCL_SYNERR_VARNAMEUNKNOWN, HCL_CNODE_GET_LOC(var), HCL_CNODE_GET_TOK(var), "unknown class-level variable name", HCL_CNODE_GET_TOKLEN(var), HCL_CNODE_GET_TOKPTR(var));
+			return -1;
+
+		}
+
 		PUSH_SUBCFRAME (hcl, COP_EMIT_SET, var); /* set doesn't evaluate the variable name */
 		cf = GET_SUBCFRAME(hcl);
 		cf->u.set.vi.type = VAR_NAMED;
@@ -3133,7 +3164,7 @@ static int compile_set_r (hcl_t* hcl, hcl_cnode_t* src)
 		if (!HCL_CNODE_IS_SYMBOL(var))
 		{
 			if (nvars > 0) break;
-			hcl_setsynerrbfmt (hcl, HCL_SYNERR_VARNAME, HCL_CNODE_GET_LOC(var), HCL_CNODE_GET_TOK(var), "variable name not a symbol in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
+			hcl_setsynerrbfmt (hcl, HCL_SYNERR_VARNAME, HCL_CNODE_GET_LOC(var), HCL_CNODE_GET_TOK(var), "variable name not symbol in %.*js", HCL_CNODE_GET_TOKLEN(cmd), HCL_CNODE_GET_TOKPTR(cmd));
 			return -1;
 		}
 
@@ -3184,6 +3215,12 @@ static int compile_set_r (hcl_t* hcl, hcl_cnode_t* src)
 
 		if (x == 0)
 		{
+			if (HCL_CNODE_IS_DSYMBOL_CLA(var))
+			{
+				hcl_setsynerrbfmt (hcl, HCL_SYNERR_VARNAMEUNKNOWN, HCL_CNODE_GET_LOC(var), HCL_CNODE_GET_TOK(var), "unknown class-level variable name", HCL_CNODE_GET_TOKLEN(var), HCL_CNODE_GET_TOKPTR(var));
+				return -1;
+			}
+
 			PUSH_SUBCFRAME (hcl, COP_EMIT_SET, var); /* set_r doesn't evaluate the variable name */
 			cf = GET_SUBCFRAME(hcl);
 			cf->u.set.vi.type = VAR_NAMED;
@@ -4057,7 +4094,7 @@ HCL_DEBUG1 (hcl, ">>>> instance variable or method %js\n", sep + 1);
 		{
 			name.ptr = sep + 1;
 			name.len -= 6;
-			x = find_variable_backward_with_word(hcl, &name, HCL_CNODE_GET_LOC(obj), 1, &vi); /* TODO: arrange to skip the current class */
+			x = find_variable_backward_with_word(hcl, &name, HCL_CNODE_GET_LOC(obj), 2, &vi); /* TODO: arrange to skip the current class */
 		}
 
 		if (x <= -1) return -1; /* error */
@@ -5261,6 +5298,8 @@ static HCL_INLINE int post_lambda (hcl_t* hcl)
 			if (x <= -1) return -1;
 			if (x == 0)
 			{
+/* TODO: handle if defun_name is DSYMOL_CLA ... */
+
 				/* arrange to save to the method slot */
 				switch (cf->u.lambda.fun_type)
 				{
diff --git a/lib/err.c b/lib/err.c
index dda436f..0ad2ea2 100644
--- a/lib/err.c
+++ b/lib/err.c
@@ -146,6 +146,8 @@ static char* synerrstr[] =
 	"too many variables defined",
 	"variable declaration disallowed",
 	"duplicate variable name",
+	"unknown variable name",
+
 	"disallowed variable name",
 	"disallowed argument name",
 	"disallowed",
diff --git a/lib/hcl-prv.h b/lib/hcl-prv.h
index c574b9c..9f203fe 100644
--- a/lib/hcl-prv.h
+++ b/lib/hcl-prv.h
@@ -174,6 +174,7 @@ enum hcl_tok_type_t
 
 	HCL_TOK_IDENT,
 	HCL_TOK_IDENT_DOTTED,
+	HCL_TOK_IDENT_DOTTED_CLA,
 	HCL_TOK_DOT,       /* . */
 	HCL_TOK_DBLDOTS,   /* .. */
 	HCL_TOK_ELLIPSIS,  /* ... */
@@ -266,6 +267,7 @@ typedef enum hcl_cnode_flagt hcl_cnode_flag_t;
 #define HCL_CNODE_SYMBOL_SYNCODE(x) ((x)->u.symbol.syncode)
 
 #define HCL_CNODE_IS_DSYMBOL(x) ((x)->cn_type == HCL_CNODE_DSYMBOL)
+#define HCL_CNODE_IS_DSYMBOL_CLA(x) ((x)->cn_type == HCL_CNODE_DSYMBOL && (x)->u.dsymbol.is_cla)
 
 #define HCL_CNODE_IS_CONS(x) ((x)->cn_type == HCL_CNODE_CONS)
 #define HCL_CNODE_IS_CONS_CONCODED(x, code) ((x)->cn_type == HCL_CNODE_CONS && (x)->u.cons.concode == (code))
@@ -296,6 +298,10 @@ struct hcl_cnode_t
 			hcl_syncode_t syncode; /* special if non-zero */
 		} symbol;
 		struct
+		{
+			int is_cla; /* class-level accessor. prefixed with self or super */
+		} dsymbol;
+		struct
 		{
 			hcl_oow_t v;
 		} smptrlit;
@@ -579,6 +585,7 @@ struct hcl_flx_pi_t
 	hcl_oow_t seg_len;
 	hcl_oow_t non_ident_seg_count;
 	hcl_tok_type_t last_non_ident_type;
+	int is_cla; /* class-level accrssor. prefixed with self/super */
 };
 
 typedef struct hcl_flx_pn_t hcl_flx_pn_t;
@@ -1723,7 +1730,7 @@ hcl_cnode_t* hcl_makecnodetrpcolons (hcl_t* hcl, int flags, const hcl_loc_t* loc
 hcl_cnode_t* hcl_makecnodedcstar (hcl_t* hcl, int flags, const hcl_loc_t* loc, const  hcl_oocs_t* tok);
 hcl_cnode_t* hcl_makecnodecharlit (hcl_t* hcl, int flags, const hcl_loc_t* loc, const  hcl_oocs_t* tok, const hcl_ooch_t v);
 hcl_cnode_t* hcl_makecnodesymbol (hcl_t* hcl, int flags, const hcl_loc_t* loc, const  hcl_oocs_t* tok);
-hcl_cnode_t* hcl_makecnodedsymbol (hcl_t* hcl, int flags, const hcl_loc_t* loc, const  hcl_oocs_t* tok);
+hcl_cnode_t* hcl_makecnodedsymbol (hcl_t* hcl, int flags, const hcl_loc_t* loc, const  hcl_oocs_t* tok, int is_cla);
 hcl_cnode_t* hcl_makecnodestrlit (hcl_t* hcl, int flags, const hcl_loc_t* loc, const  hcl_oocs_t* tok);
 hcl_cnode_t* hcl_makecnodenumlit (hcl_t* hcl, int flags, const hcl_loc_t* loc, const  hcl_oocs_t* tok);
 hcl_cnode_t* hcl_makecnoderadnumlit (hcl_t* hcl, int flags, const hcl_loc_t* loc, const  hcl_oocs_t* tok);
diff --git a/lib/hcl.h b/lib/hcl.h
index f8d13ce..18d5ce2 100644
--- a/lib/hcl.h
+++ b/lib/hcl.h
@@ -150,6 +150,7 @@ enum hcl_synerrnum_t
 	HCL_SYNERR_VARFLOOD,      /* too many variables defined */
 	HCL_SYNERR_VARDCLBANNED,  /* variable declaration disallowed */
 	HCL_SYNERR_VARNAMEDUP,    /* duplicate variable name */
+	HCL_SYNERR_VARNAMEUNKNOWN, /* unknown variable name */
 
 	HCL_SYNERR_BANNEDVARNAME, /* disallowed varible name */
 	HCL_SYNERR_BANNEDARGNAME, /* disallowed argument name */
diff --git a/lib/read.c b/lib/read.c
index c9f1b57..889e939 100644
--- a/lib/read.c
+++ b/lib/read.c
@@ -1452,7 +1452,11 @@ static int feed_process_token (hcl_t* hcl)
 			goto auto_xlist;
 
 		case HCL_TOK_IDENT_DOTTED:
-			frd->obj = hcl_makecnodedsymbol(hcl, 0, TOKEN_LOC(hcl), TOKEN_NAME(hcl));
+			frd->obj = hcl_makecnodedsymbol(hcl, 0, TOKEN_LOC(hcl), TOKEN_NAME(hcl), 0);
+			goto auto_xlist;
+
+		case HCL_TOK_IDENT_DOTTED_CLA:
+			frd->obj = hcl_makecnodedsymbol(hcl, 0, TOKEN_LOC(hcl), TOKEN_NAME(hcl), 1);
 			goto auto_xlist;
 
 		auto_xlist:
@@ -2165,7 +2169,7 @@ static int flx_plain_ident (hcl_t* hcl, hcl_ooci_t c) /* identifier */
 			if (pi->seg_count == 0 && (tok_type == HCL_TOK_SELF || tok_type == HCL_TOK_SUPER))
 			{
 				/* allowed if it begins with self. or super. */
-				/* nothing to do */
+				pi->is_cla = 1; /* mark that it's prefixed with self or super */
 			}
 			else
 			{
@@ -2202,7 +2206,8 @@ static int flx_plain_ident (hcl_t* hcl, hcl_ooci_t c) /* identifier */
 
 		/* if single-segmented, perform classification(call classify_ident_token()) again
 		 * bcause self and super as the first segment have not been marked as a non-identifier above */
-		tok_type = (pi->seg_count == 1? classify_ident_token(hcl, TOKEN_NAME(hcl)): HCL_TOK_IDENT_DOTTED);
+		tok_type = (pi->seg_count == 1? classify_ident_token(hcl, TOKEN_NAME(hcl)):
+		            (pi->is_cla? HCL_TOK_IDENT_DOTTED_CLA: HCL_TOK_IDENT_DOTTED));
 		FEED_WRAP_UP (hcl, tok_type);
 		goto not_consumed;
 	}
diff --git a/t/Makefile.am b/t/Makefile.am
index 929c1e5..5c1c2fc 100644
--- a/t/Makefile.am
+++ b/t/Makefile.am
@@ -9,6 +9,7 @@ check_SCRIPTS = \
 	va-01.hcl
 
 check_ERRORS = \
+	class-01.err \
 	do-01.err \
 	do-02.err \
 	feed-01.err \
diff --git a/t/Makefile.in b/t/Makefile.in
index 150455c..36cb5a2 100644
--- a/t/Makefile.in
+++ b/t/Makefile.in
@@ -480,6 +480,7 @@ check_SCRIPTS = \
 	va-01.hcl
 
 check_ERRORS = \
+	class-01.err \
 	do-01.err \
 	do-02.err \
 	feed-01.err \
diff --git a/t/class-01.err b/t/class-01.err
new file mode 100644
index 0000000..6436ff0
--- /dev/null
+++ b/t/class-01.err
@@ -0,0 +1,23 @@
+defclass B | x y | {
+
+};
+
+defclass X ::: B | a b | {
+	defun ::* new(t) {
+		| a |
+		set self.a t;
+		set a 100;
+		set self.b (* t 2);
+
+		set self.c (fun(b) {  ##ERROR: syntax error - unknown class-level variable name
+			printf "xxxx [%d]\n" b;
+		});
+		return self;
+	};
+
+	defun print() {
+		self.c (+ self.a self.b);
+		printf "a=%d b=%d\n" self.a self.b;
+	}
+};
+