diff --git a/src/c/character.d b/src/c/character.d
index cf86d72ba..8843ba0f5 100644
--- a/src/c/character.d
+++ b/src/c/character.d
@@ -465,9 +465,22 @@ cl_char_name(cl_object c)
 	ecl_character code = ecl_char_code(c);
 	cl_object output;
 	if (code > 127) {
-		char name[20]; /* cleanup */
-		sprintf(name, "U%04x", code);
-		output = make_base_string_copy(name);
+		char name[7];
+                char *start;
+                name[7] = 0;
+                name[6] = ecl_digit_char(code & 0xF, 16); code >>= 4;
+                name[5] = ecl_digit_char(code & 0xF, 16); code >>= 4;
+                name[4] = ecl_digit_char(code & 0xF, 16); code >>= 4;
+                name[3] = ecl_digit_char(code & 0xF, 16); code >>= 4;
+                if (code == 0) {
+                        start = name + 2;
+                } else {
+                        name[2] = ecl_digit_char(code & 0xF, 16); code >>= 4;
+                        name[1] = ecl_digit_char(code & 0xF, 16);
+                        start = name;
+                }
+                start[0] = 'U';
+		output = make_base_string_copy(start);
 	} else {
 		output = ecl_gethash_safe(MAKE_FIXNUM(code), cl_core.char_names, Cnil);
 	}
diff --git a/src/c/printer/write_sse.d b/src/c/printer/write_sse.d
index 0d0d004b8..8a919cdb5 100644
--- a/src/c/printer/write_sse.d
+++ b/src/c/printer/write_sse.d
@@ -31,12 +31,12 @@ is_all_FF(void *ptr, int size) {
 static void
 write_sse_float(float v, cl_object stream)
 {
-	if (is_all_FF(&v, sizeof(float)))
+	if (is_all_FF(&v, sizeof(float))) {
 		writestr_stream(" TRUE", stream);
-	else {
-		char buf[60];
-		sprintf(buf, " %g", v);
-		writestr_stream(buf, stream);
+	} else {
+                ecl_def_ct_single_float(wrapped_f, v, ,);
+                ecl_write_char(' ', stream);
+                si_write_ugly_object(wrapped_f, stream);
 	}
 }
 
@@ -46,9 +46,9 @@ write_sse_double(double v, cl_object stream)
 	if (is_all_FF(&v, sizeof(double)))
 		writestr_stream(" TRUE", stream);
         else {
-		char buf[60];
-		sprintf(buf, " %lg", v);
-		writestr_stream(buf, stream);
+                ecl_def_ct_double_float(wrapped_f, v, ,);
+                ecl_write_char(' ', stream);
+                si_write_ugly_object(wrapped_f, stream);
 	}
 }
 
@@ -74,14 +74,20 @@ write_sse_pack(cl_object x, cl_object stream)
 		write_sse_double(x->sse.data.df[0], stream);
 		write_sse_double(x->sse.data.df[1], stream);
 		break;
-	default:
+	default: {
+                cl_object buffer = si_get_buffer_string();
 		for (i = 0; i < 16; i++) {
 			char buf[10];
 			int pad = 1 + (i%4 == 0);
-			sprintf(buf, "%*c%02x", pad, ' ', x->sse.data.b8[i]);
-			writestr_stream(buf, stream);
+                        ecl_string_push_extend(' ', buffer);
+                        if (i%4 == 0) ecl_string_push_extend(' ', buffer);
+                        si_integer_to_string(buffer, MAKE_FIXNUM(x->sse.data.b8[i]),
+                                             MAKE_FIXNUM(16), Cnil, Cnil);
 		}
-		break;
+                si_do_write_sequence(buffer, stream, MAKE_FIXNUM(0), Cnil);
+                si_put_buffer_string(buffer);
+                break;
+        }
 	}
 }
 
diff --git a/src/c/printer/write_ugly.d b/src/c/printer/write_ugly.d
index a75a2251d..63251d03c 100644
--- a/src/c/printer/write_ugly.d
+++ b/src/c/printer/write_ugly.d
@@ -127,15 +127,9 @@ write_character(cl_object x, cl_object stream)
 		ecl_write_char(i, stream);
 	} else {
 		writestr_stream("#\\", stream);
-		if (i < 32 || i == 127) {
+		if (i < 32 || i >= 127) {
 			cl_object name = cl_char_name(CODE_CHAR(i));
 			writestr_stream((char*)name->base_string.self, stream);
-		} else if (i >= 128) {
-                        int  index = 0;
-			char name[20];
-			sprintf(name, "U%04x", i); /* cleanup */
-                        while(name[index])
-				ecl_write_char(name[index++], stream);
 		} else {
 			ecl_write_char(i, stream);
 		}