diff --git a/test/unit/utf8.c b/test/unit/utf8.c
index a96ebaea..09f1a1a4 100644
--- a/test/unit/utf8.c
+++ b/test/unit/utf8.c
@@ -83,6 +83,8 @@ static void TEST_utf8_boundary_conditions(void)
 
 static void TEST_utf8_malformed_sequences(void)
 {
+	char buf[100];
+	int i;
 	/* 3  Malformed sequences */
 	/* 3.1  Unexpected continuation bytes */
 	utf8_helper("3.1.1  First continuation byte 0x80: \"�\"", MOSQ_ERR_MALFORMED_UTF8);
@@ -95,32 +97,82 @@ static void TEST_utf8_malformed_sequences(void)
 	utf8_helper("3.1.8  7 continuation bytes: \"�������\"", MOSQ_ERR_MALFORMED_UTF8);
 
 	/* 3.1.9  Sequence of all 64 possible continuation bytes (0x80-0xbf): */
-	utf8_helper("����������������", MOSQ_ERR_MALFORMED_UTF8);
-    utf8_helper("����������������", MOSQ_ERR_MALFORMED_UTF8);
-    utf8_helper("����������������", MOSQ_ERR_MALFORMED_UTF8);
-    utf8_helper("����������������\"", MOSQ_ERR_MALFORMED_UTF8);
+	memset(buf, 0, sizeof(buf));
+	for(i=0x80; i<0x90; i++){
+		buf[i-0x80] = i;
+	}
+	utf8_helper(buf, MOSQ_ERR_MALFORMED_UTF8);
+	memset(buf, 0, sizeof(buf));
+	for(i=0x90; i<0xa0; i++){
+		buf[i-0x90] = i;
+	}
+	utf8_helper(buf, MOSQ_ERR_MALFORMED_UTF8);
+
+	for(i=0x80; i<0xA0; i++){
+		buf[0] = i;
+		buf[1] = 0;
+		utf8_helper(buf, MOSQ_ERR_MALFORMED_UTF8);
+	}
+
+	for(i=0xA0; i<0xC0; i++){
+		buf[0] = i;
+		buf[1] = 0;
+		utf8_helper(buf, MOSQ_ERR_MALFORMED_UTF8);
+	}
 
 	/* 3.2  Lonely start characters */
 
 	/* 3.2.1  All 32 first bytes of 2-byte sequences (0xc0-0xdf),
        each followed by a space character: */
-	utf8_helper("\"� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � \"", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � ", MOSQ_ERR_MALFORMED_UTF8);
+	for(i=0xC0; i<0xE0; i++){
+		buf[0] = i;
+		buf[1] = ' ';
+		buf[2] = 0;
+		utf8_helper(buf, MOSQ_ERR_MALFORMED_UTF8);
+	}
 
 	/* 3.2.2  All 16 first bytes of 3-byte sequences (0xe0-0xef),
        each followed by a space character: */
 	utf8_helper("\"� � � � � � � � � � � � � � � � \"", MOSQ_ERR_MALFORMED_UTF8);
+	for(i=0xe0; i<0xf0; i++){
+		buf[0] = i;
+		buf[1] = ' ';
+		buf[2] = 0;
+		utf8_helper(buf, MOSQ_ERR_MALFORMED_UTF8);
+	}
 
 	/* 3.2.3  All 8 first bytes of 4-byte sequences (0xf0-0xf7),
        each followed by a space character: */
 	utf8_helper("\"� � � � � � � � \"", MOSQ_ERR_MALFORMED_UTF8);
+	for(i=0xF0; i<0xF8; i++){
+		buf[0] = i;
+		buf[1] = ' ';
+		buf[2] = 0;
+		utf8_helper(buf, MOSQ_ERR_MALFORMED_UTF8);
+	}
 
 	/* 3.2.4  All 4 first bytes of 5-byte sequences (0xf8-0xfb),
        each followed by a space character: */
 	utf8_helper("\"� � � � \"", MOSQ_ERR_MALFORMED_UTF8);
+	for(i=0xF8; i<0xFC; i++){
+		buf[0] = i;
+		buf[1] = ' ';
+		buf[2] = 0;
+		utf8_helper(buf, MOSQ_ERR_MALFORMED_UTF8);
+	}
 
 	/* 3.2.5  All 2 first bytes of 6-byte sequences (0xfc-0xfd),
        each followed by a space character: */
 	utf8_helper("\"� � \"", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("� ", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("� ", MOSQ_ERR_MALFORMED_UTF8);
+	for(i=0xFC; i<0xFE; i++){
+		buf[0] = i;
+		buf[1] = ' ';
+		buf[2] = 0;
+		utf8_helper(buf, MOSQ_ERR_MALFORMED_UTF8);
+	}
 
 	/* 3.3  Sequences with last continuation byte missing
 
@@ -239,7 +291,6 @@ static void TEST_utf8_illegal_code_positions(void)
 
 	/* 5.2 Paired UTF-16 surrogates */
 
-	/* FIXME - these need splitting up into separate tests. */
 	utf8_helper("5.2.1  U+D800 U+DC00 = ed a0 80 ed b0 80 = \"������\"", MOSQ_ERR_MALFORMED_UTF8);
 	utf8_helper("5.2.2  U+D800 U+DFFF = ed a0 80 ed bf bf = \"������\"", MOSQ_ERR_MALFORMED_UTF8);
 	utf8_helper("5.2.3  U+DB7F U+DC00 = ed ad bf ed b0 80 = \"������\"", MOSQ_ERR_MALFORMED_UTF8);
@@ -277,10 +328,73 @@ static void TEST_utf8_illegal_code_positions(void)
 
 	/* FIXME - these need splitting up into separate tests. */
 	utf8_helper("5.3.3  U+FDD0 .. U+FDEF = \"﷐﷑﷒﷓﷔﷕﷖﷗﷘﷙﷚﷛﷜﷝﷞﷟﷠﷡﷢﷣﷤﷥﷦﷧﷨﷩﷪﷫﷬﷭﷮﷯\"", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷐", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷑", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷒", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷓", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷔", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷕", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷖", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷗", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷘", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷙", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷚", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷛", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷜", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷝", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷞", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷟", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷠", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷡", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷢", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷣", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷤", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷥", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷦", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷧", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷨", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷩", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷪", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷫", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷬", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷭", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷮", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("﷯", MOSQ_ERR_MALFORMED_UTF8);
 
 	/* 5.3.4  U+nFFFE U+nFFFF (for n = 1..10) */
 
-	utf8_helper("\"🿾🿿𯿾𯿿𿿾𿿿񏿾񏿿񟿾񟿿񯿾񯿿񿿾񿿿򏿾򏿿򟿾򟿿򯿾򯿿򿿾򿿿󏿾󏿿󟿾󟿿󯿾󯿿󿿾󿿿􏿾􏿿\"", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("🿾", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("🿿", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("𯿾", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("𯿿", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("𿿾", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("𿿿", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("񏿾", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("񏿿", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("񟿾", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("񟿿", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("񯿾", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("񯿿", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("񿿾", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("񿿿", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("򏿾", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("򏿿", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("򟿾", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("򟿿", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("򯿾", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("򯿿", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("򿿾", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("򿿿", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("󏿾", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("󏿿", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("󟿾", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("󟿿", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("󯿾", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("󯿿", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("󿿾", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("󿿿", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("􏿾", MOSQ_ERR_MALFORMED_UTF8);
+	utf8_helper("􏿿", MOSQ_ERR_MALFORMED_UTF8);
 }