diff --git a/qse/cmd/sed/sed.c b/qse/cmd/sed/sed.c
index 8e5fab11..2d5f5757 100644
--- a/qse/cmd/sed/sed.c
+++ b/qse/cmd/sed/sed.c
@@ -67,7 +67,7 @@ static qse_ssize_t in (
 					qse_sed_getmmgr(sed),
 					0,
 					file,
-					QSE_SIO_READ
+					QSE_SIO_READ | QSE_SIO_IGNOREMBWCERR
 				);	
 
 				if (arg->handle == QSE_NULL) return -1;
@@ -107,7 +107,8 @@ static qse_ssize_t out (
 					arg->path,
 					QSE_SIO_WRITE |
 					QSE_SIO_CREATE |
-					QSE_SIO_TRUNCATE
+					QSE_SIO_TRUNCATE | 
+					QSE_SIO_IGNOREMBWCERR
 				);	
 
 				if (arg->handle == QSE_NULL) return -1;
@@ -247,7 +248,11 @@ qse_char_t* load_script_file (qse_sed_t* sed, const qse_char_t* file)
 	fp = qse_sio_open (
 		qse_sed_getmmgr(sed), 0, file, 
 		QSE_SIO_READ | QSE_SIO_IGNOREMBWCERR);
-	if (fp == QSE_NULL) return QSE_NULL;
+	if (fp == QSE_NULL) 
+	{
+		qse_fprintf (QSE_STDERR, QSE_T("ERROR: cannot open %s\n"), file);
+		return QSE_NULL;
+	}
 
 	if (qse_str_init (&script, QSE_MMGR_GETDFL(), 1024) <= -1)
 	{
diff --git a/qse/lib/cmn/sio.c b/qse/lib/cmn/sio.c
index 9d89a63b..b3e23597 100644
--- a/qse/lib/cmn/sio.c
+++ b/qse/lib/cmn/sio.c
@@ -1,5 +1,5 @@
 /*
- * $Id: sio.c 565 2011-09-11 02:48:21Z hyunghwan.chung $
+ * $Id: sio.c 566 2011-09-11 12:44:56Z hyunghwan.chung $
  *
     Copyright 2006-2011 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -56,7 +56,7 @@ static qse_sio_t __sio_in =
 	{
 		QSE_NULL,
 		0,
-		0,
+		QSE_TIO_IGNOREMBWCERR,
 
 		__sio_input,
 		__sio_output,
@@ -98,7 +98,7 @@ static qse_sio_t __sio_out =
 	{
 		QSE_NULL,
 		0,
-		0,
+		QSE_TIO_IGNOREMBWCERR,
 
 		__sio_input,
 		__sio_output,
@@ -140,7 +140,7 @@ static qse_sio_t __sio_err =
 	{
 		QSE_NULL,
 		0,
-		0, 
+		QSE_TIO_IGNOREMBWCERR,
 
 		__sio_input,
 		__sio_output,
diff --git a/qse/lib/cmn/tio-get.c b/qse/lib/cmn/tio-get.c
index 3320ecb3..26a92af9 100644
--- a/qse/lib/cmn/tio-get.c
+++ b/qse/lib/cmn/tio-get.c
@@ -1,5 +1,5 @@
 /*
- * $Id: tio-get.c 565 2011-09-11 02:48:21Z hyunghwan.chung $
+ * $Id: tio-get.c 566 2011-09-11 12:44:56Z hyunghwan.chung $
  *
     Copyright 2006-2011 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -55,7 +55,8 @@ static qse_ssize_t tio_getc (qse_tio_t* tio, qse_char_t* c)
 			&tio->inbuf[left], QSE_COUNTOF(tio->inbuf)-left);
 		if (n == 0) 
 		{
-			if (tio->inbuf_curp < tio->inbuf_len)
+			if (tio->inbuf_curp < tio->inbuf_len &&
+			    !(tio->flags & QSE_TIO_IGNOREMBWCERR))
 			{
 				/* gargage left in the buffer */
 				tio->errnum = QSE_TIO_EICSEQ;
@@ -86,7 +87,9 @@ static qse_ssize_t tio_getc (qse_tio_t* tio, qse_char_t* c)
 		/* illegal sequence */
 		if (tio->flags & QSE_TIO_IGNOREMBWCERR)
 		{
-			*c = tio->inbuf[tio->inbuf_curp++];
+			/* *c = tio->inbuf[tio->inbuf_curp++]; */
+			*c = QSE_WT('?');
+			tio->inbuf_curp++;
 			return 1;
 		}
 
diff --git a/qse/lib/cmn/tio-put.c b/qse/lib/cmn/tio-put.c
index 0fa674e9..6b13daba 100644
--- a/qse/lib/cmn/tio-put.c
+++ b/qse/lib/cmn/tio-put.c
@@ -1,5 +1,5 @@
 /*
- * $Id: tio-put.c 565 2011-09-11 02:48:21Z hyunghwan.chung $
+ * $Id: tio-put.c 566 2011-09-11 12:44:56Z hyunghwan.chung $
  *
     Copyright 2006-2011 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -62,6 +62,7 @@ static qse_ssize_t tio_putc (qse_tio_t* tio, qse_char_t c, int* flush_needed)
 	}
 	else if (n > QSE_COUNTOF(mc))
 	{
+		if (tio->flags & QSE_TIO_IGNOREMBWCERR) return 1;
 		tio->errnum = QSE_TIO_ENOSPC;
 		return -1;
 	}
diff --git a/qse/lib/sed/sed.c b/qse/lib/sed/sed.c
index 89a75694..b0053e9d 100644
--- a/qse/lib/sed/sed.c
+++ b/qse/lib/sed/sed.c
@@ -1,5 +1,5 @@
 /*
- * $Id: sed.c 564 2011-09-10 16:14:38Z hyunghwan.chung $
+ * $Id: sed.c 566 2011-09-11 12:44:56Z hyunghwan.chung $
  *
     Copyright 2006-2011 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -145,7 +145,6 @@ int qse_sed_getoption (qse_sed_t* sed)
 	return sed->option;
 }
 
-
 #ifdef USE_REX
 qse_size_t qse_sed_getmaxdepth (qse_sed_t* sed, qse_sed_depth_t id)
 {
@@ -1015,60 +1014,6 @@ static int get_subst (qse_sed_t* sed, qse_sed_cmd_t* cmd)
 
 	if (pickup_rex (sed, delim, 1, cmd, t[0]) <= -1) goto oops;
 	if (pickup_rex (sed, delim, 0, cmd, t[1]) <= -1) goto oops;
-#if 0
-/* calling pickup_rex twice above instead of commenting out this part */
-	for (i = 0; i < 2; i++)
-	{
-		c = NXTSC (sed);
-
-		while (c != delim)
-		{
-			CHECK_CMDIC (sed, cmd, c, goto oops);
-
-			if (c == QSE_T('\\'))
-			{
-				qse_cint_t nc;
-
-				nc = NXTSC (sed);
-				CHECK_CMDIC_ESCAPED (sed, cmd, nc, goto oops);
-
-				if (nc == QSE_T('\n')) c = nc;
-				else
-				{
-					qse_cint_t ec;
-	
-					/* Escaping a known speical character for the regular expression 
-					 * part is done here. However, Escaping a special character for 
-					 * the replacement part is done in do_subst() except '\n' because
-					 * it has more special characters like '&'. */
-
-					ec = trans_escaped (nc);
-					if (ec == nc)
-					{
-						/* if the character after a backslash is not special at the
-						 * this layer, add the backslash into the regular expression
-						 * buffer as it is. */
-						if (qse_str_ccat (t[i], QSE_T('\\')) == (qse_size_t)-1)
-						{
-							SETERR0 (sed, QSE_SED_ENOMEM, QSE_NULL);
-							goto oops;
-						}
-					}
-
-					c = ec;
-				}
-			}
-
-			if (qse_str_ccat (t[i], c) == (qse_size_t)-1)
-			{
-				SETERR0 (sed, QSE_SED_ENOMEM, QSE_NULL);
-				goto oops;
-			}
-
-			c = NXTSC (sed);
-		}	
-	}
-#endif
 
 	/* skip spaces before options */
 	do { c = NXTSC(sed); } while (IS_SPACE(c));
diff --git a/qse/lib/sed/std.c b/qse/lib/sed/std.c
index 066fa7f7..9e2a44e5 100644
--- a/qse/lib/sed/std.c
+++ b/qse/lib/sed/std.c
@@ -84,7 +84,7 @@ static qse_ssize_t xin (
 						sed->mmgr,
 						0,
 						xtn->infile,
-						QSE_SIO_READ
+						QSE_SIO_READ | QSE_SIO_IGNOREMBWCERR
 					);
 					if (sio == QSE_NULL)
 					{
@@ -105,7 +105,7 @@ static qse_ssize_t xin (
 					sed->mmgr,
 					0,
 					arg->path,
-					QSE_SIO_READ
+					QSE_SIO_READ | QSE_SIO_IGNOREMBWCERR
 				);
 			}
 
@@ -167,7 +167,8 @@ static qse_ssize_t xout (
 						xtn->outfile,
 						QSE_SIO_WRITE |
 						QSE_SIO_CREATE |
-						QSE_SIO_TRUNCATE
+						QSE_SIO_TRUNCATE |
+						QSE_SIO_IGNOREMBWCERR
 					);
 					if (sio == QSE_NULL)
 					{
@@ -190,7 +191,8 @@ static qse_ssize_t xout (
 					arg->path,
 					QSE_SIO_WRITE |
 					QSE_SIO_CREATE |
-					QSE_SIO_TRUNCATE
+					QSE_SIO_TRUNCATE |
+					QSE_SIO_IGNOREMBWCERR
 				);
 			}