diff --git a/cmd_parser.c b/cmd_parser.c
index 6f631cc..21ff7a8 100644
--- a/cmd_parser.c
+++ b/cmd_parser.c
@@ -50,6 +50,7 @@ __xdata char port_names[9][PORT_NAME_SIZE];
 extern __xdata uint16_t management_vlan;
 extern __xdata uint8_t sfp_speed[2];
 extern __xdata uint8_t sfp_pins_last;
+extern __xdata uint8_t sfp_options[2];
 __xdata uint8_t gpio_last_value[8] = { 0 };
 
 // Temporatly for str to hex convertion value.
@@ -741,7 +742,7 @@ void parse_mtu(void)
 void sfp_print_measurements(uint8_t sfp)
 {
 	print_string("Options: "); print_byte(sfp_read_reg(sfp, 92)); write_char('\n');
-	if (!(sfp_read_reg(sfp, 92) & 0x40))
+	if (!(sfp_options[sfp] & 0x40))
 		return;
 	print_string("Temp: "); print_byte(sfp_read_reg(sfp, 224)); print_byte(sfp_read_reg(sfp, 225)); write_char('\n');
 	print_string("Vcc: "); print_byte(sfp_read_reg(sfp, 226)); print_byte(sfp_read_reg(sfp, 227)); write_char('\n');
diff --git a/httpd/httpd.c b/httpd/httpd.c
index c05a7e1..0a861a3 100644
--- a/httpd/httpd.c
+++ b/httpd/httpd.c
@@ -101,21 +101,6 @@ uint8_t find_entry(__xdata uint8_t *e)
 }
 
 
-char strcmp(__xdata uint8_t *c, __code uint8_t * __xdata d)
-{
-	uint8_t i = 0;
-
-	while (d[i] && (d[i] == c[i]))
-		i++;
-
-	if (c[i] < d[i])
-		return -1;
-	else if (c[i] > d[i])
-		return 1;
-	return 0;
-}
-
-
 bool is_word(__xdata uint8_t *xdata_str_p, __code uint8_t * __xdata code_str_p)
 {
 	uint8_t u, c;
diff --git a/httpd/page_impl.c b/httpd/page_impl.c
index 66b234e..7ca29e4 100644
--- a/httpd/page_impl.c
+++ b/httpd/page_impl.c
@@ -660,52 +660,53 @@ void send_status(void)
 		slen += strtox(outbuf + slen, "\"");
 
 		if (machine.is_sfp[i]) {
+			uint8_t sfp = machine.is_sfp[i] - 1;
 			slen += strtox(outbuf + slen, ",\"isSFP\":1,\"enabled\":");
-			if (!(sfp_pins_last & (0x1 << ((machine.is_sfp[i] - 1) << 2)))) {
+			if (!(sfp_pins_last & (0x1 << (sfp << 2)))) {
 				bool_to_html(1);
 				slen += strtox(outbuf + slen,",\"sfp_options\":\"0x");
-				byte_to_html(sfp_options[machine.is_sfp[i]-1]);
-				if (sfp_options[machine.is_sfp[i]-1] & 0x40) {
+				byte_to_html(sfp_options[sfp]);
+				if (sfp_options[sfp] & 0x40) {
 					slen += strtox(outbuf + slen,"\",\"sfp_temp\":\"0x");
-					sfp_send_data(machine.is_sfp[i] - 1, 224, 2);
+					sfp_send_data(sfp, 224, 2);
 					slen += strtox(outbuf + slen,"\",\"sfp_vcc\":\"0x");
-					sfp_send_data(machine.is_sfp[i] - 1, 226, 2);
+					sfp_send_data(sfp, 226, 2);
 					slen += strtox(outbuf + slen,"\",\"sfp_txbias\":\"0x");
-					sfp_send_data(machine.is_sfp[i] - 1, 228, 2);
+					sfp_send_data(sfp, 228, 2);
 					slen += strtox(outbuf + slen,"\",\"sfp_txpower\":\"0x");
-					sfp_send_data(machine.is_sfp[i] - 1, 230, 2);
+					sfp_send_data(sfp, 230, 2);
 					slen += strtox(outbuf + slen,"\",\"sfp_rxpower\":\"0x");
-					sfp_send_data(machine.is_sfp[i] - 1, 232, 2);
-					if (sfp_options[machine.is_sfp[i]-1] & 0x10) {
+					sfp_send_data(sfp, 232, 2);
+					if (sfp_options[sfp] & 0x10) {
 						slen += strtox(outbuf + slen,"\",\"sfp_temp_cal\":\"0x");
-						sfp_send_data(machine.is_sfp[i] - 1, 212, 4);
+						sfp_send_data(sfp, 212, 4);
 						slen += strtox(outbuf + slen,"\",\"sfp_vcc_cal\":\"0x");
-						sfp_send_data(machine.is_sfp[i] - 1, 216, 4);
+						sfp_send_data(sfp, 216, 4);
 						slen += strtox(outbuf + slen,"\",\"sfp_txbias_cal\":\"0x");
-						sfp_send_data(machine.is_sfp[i] - 1, 204, 4);
+						sfp_send_data(sfp, 204, 4);
 						slen += strtox(outbuf + slen,"\",\"sfp_txpower_cal\":\"0x");
-						sfp_send_data(machine.is_sfp[i] - 1, 208, 4);
+						sfp_send_data(sfp, 208, 4);
 						slen += strtox(outbuf + slen,"\",\"sfp_rxpower_cal\":\"0x");
-						sfp_send_data(machine.is_sfp[i] - 1, 184, 16);
-						sfp_send_data(machine.is_sfp[i] - 1, 200, 4);
+						sfp_send_data(sfp, 184, 16);
+						sfp_send_data(sfp, 200, 4);
 					}
 					slen += strtox(outbuf + slen,"\",\"sfp_state\":\"0x");
-					sfp_send_data(machine.is_sfp[i] - 1, 238, 1);
+					sfp_send_data(sfp, 238, 1);
 				}
 				slen += strtox(outbuf + slen,"\",\"sfp_vendor\":\"");
-				for (register uint8_t s = 0; s < 16; s++)
-					outbuf[slen++] = sfp_module_vendor[machine.is_sfp[i]-1][s];
+				for (register uint8_t s = 0; s < 16 && sfp_module_vendor[sfp][s]; s++)
+					outbuf[slen++] = sfp_module_vendor[sfp][s];
 				slen += strtox(outbuf + slen,"\",\"sfp_model\":\"");
-				for (register uint8_t s = 0; s < 16; s++)
-					outbuf[slen++] = sfp_module_model[machine.is_sfp[i]-1][s];
+				for (register uint8_t s = 0; s < 16 && sfp_module_model[sfp][s]; s++)
+					outbuf[slen++] = sfp_module_model[sfp][s];
 				slen += strtox(outbuf + slen,"\",\"sfp_serial\":\"");
-				for (register uint8_t s = 0; s < 16; s++)
-					outbuf[slen++] = sfp_module_serial[machine.is_sfp[i]-1][s];
+				for (register uint8_t s = 0; s < 16 && sfp_module_serial[sfp][s]; s++)
+					outbuf[slen++] = sfp_module_serial[sfp][s];
 				slen += strtox(outbuf + slen,"\",\"sfp_los\":");
-				if (machine.sfp_port[machine.is_sfp[i]-1].pin_los == GPIO_NA) {
+				if (machine.sfp_port[sfp].pin_los == GPIO_NA) {
 					slen += strtox(outbuf + slen,"null");
 				} else {
-					bool_to_html(sfp_pins_last & (0x2 << (((machine.is_sfp[i]-1) << 2))));
+					bool_to_html(sfp_pins_last & (0x2 << (sfp << 2)));
 				}
 			} else {
 				bool_to_html(0);
diff --git a/rtl837x_common.h b/rtl837x_common.h
index 6d6abb5..9aa9af4 100644
--- a/rtl837x_common.h
+++ b/rtl837x_common.h
@@ -158,6 +158,7 @@ uint16_t strlen(register __code const char *s);
 uint16_t strlen_x(register __xdata const char *s);
 uint16_t strtox(register __xdata uint8_t *dst, register __code const char *s);
 uint16_t strcpy(register __xdata uint8_t *dst, register const char *s);
+char strcmp(register __xdata const uint8_t *a, register __code const uint8_t *b);
 void tcpip_output(void);
 uint8_t read_flash(uint8_t bank, __code uint8_t *addr);
 void get_random_32(void);
diff --git a/rtlplayground.c b/rtlplayground.c
index 356ea9c..30b15d8 100644
--- a/rtlplayground.c
+++ b/rtlplayground.c
@@ -138,10 +138,25 @@ __xdata char sfp_module_model[2][17];
 __xdata char sfp_module_serial[2][17];
 __xdata uint8_t sfp_options[2];
 __xdata uint8_t sfp_speed[2];
+__xdata uint8_t sfp_quirks[2];
 __xdata bool button_last;
 __xdata uint8_t button_sec_counter_last;
 volatile __bit tx_buf_empty;
 
+__code enum sfp_quirk {
+	SFP_QUIRK_DDM = (1 << 0),
+};
+
+struct sfp_quirk_entry {
+	__code char *vendor; // Set vendor or model to 0 to act as wildcard
+	__code char *model;
+	uint8_t quirks;
+};
+
+static __code struct sfp_quirk_entry sfp_quirk_table[] = {
+	{ "QSFPTEK", "QT-SFP+-T", SFP_QUIRK_DDM },
+};
+
 struct eth_in {
 	struct uip_eth_addr dst;
 	struct uip_eth_addr src;
@@ -327,6 +342,21 @@ uint16_t strlen_x(register __xdata const char *s)
 }
 
 
+char strcmp(register __xdata const uint8_t *a, register __code const uint8_t *b)
+{
+	uint8_t i = 0;
+
+	while (b[i] && (b[i] == a[i]))
+		i++;
+
+	if (a[i] < b[i])
+		return -1;
+	else if (a[i] > b[i])
+		return 1;
+	return 0;
+}
+
+
 void print_short(uint16_t a)
 {
 	// allocating the registers first improves the sdcc code here
@@ -1199,18 +1229,46 @@ void sfp_print_info(uint8_t sfp)
 	print_string("\n");
 }
 
+// Normalize strings from EEPROM by removing any trailing spaces; this allows simpler comparisons
+void sfp_read_field(__xdata char *dst, uint8_t sfp, uint8_t start, uint8_t length) __reentrant
+{
+	dst[length] = '\0';
+
+	for (uint8_t i = 0; i < length; i++)
+		dst[i] = sfp_read_reg(sfp, start + i);
+
+	while (length > 0 && dst[--length] == ' ')
+		dst[length] = '\0';
+}
 
 void sfp_get_info(uint8_t sfp)
 {
-	for (uint8_t i = 20; i < 36; i++)
-		sfp_module_vendor[sfp][i-20] = sfp_read_reg(sfp, i);
-	sfp_module_vendor[sfp][16] = '\0';
-	for (uint8_t i = 40; i < 56; i++)
-		sfp_module_model[sfp][i-40] = sfp_read_reg(sfp, i);
-	sfp_module_model[sfp][16] = '\0';
-	for (uint8_t i = 68; i < 84; i++)
-		sfp_module_serial[sfp][i-68] = sfp_read_reg(sfp, i);
-	sfp_module_serial[sfp][16] = '\0';
+	sfp_read_field(sfp_module_vendor[sfp], sfp, 20, 16);
+	sfp_read_field(sfp_module_model[sfp], sfp, 40, 16);
+	sfp_read_field(sfp_module_serial[sfp], sfp, 68, 16);
+}
+
+void sfp_apply_quirks(uint8_t sfp) __reentrant
+{
+	sfp_quirks[sfp] = 0;
+
+	for (uint8_t i = 0; i < sizeof(sfp_quirk_table) / sizeof(*sfp_quirk_table); i++) {
+		if (!sfp_quirk_table[i].vendor || !strcmp(sfp_module_vendor[sfp], sfp_quirk_table[i].vendor)) {
+			if (!sfp_quirk_table[i].model || !strcmp(sfp_module_model[sfp], sfp_quirk_table[i].model)) {
+				sfp_quirks[sfp] |= sfp_quirk_table[i].quirks;
+			}
+		}
+	}
+
+	if (sfp_quirks[sfp] & SFP_QUIRK_DDM) {
+		if (!(sfp_options[sfp] & 0x40)) {
+			// The module reports that DDM is not implemented, but try a dummy read to confirm
+			// 0xff would mean a failed I2C read or an impossible (per spec) voltage greater than 6.5V
+			if (sfp_read_reg(sfp, 226) != 0xff) {
+				sfp_options[sfp] |= 0x40;
+			}
+		}
+	}
 }
 
 
@@ -1255,6 +1313,7 @@ void handle_sfp(void)
 				print_string("\n");
 				sfp_options[sfp] = sfp_read_reg(sfp, 92);
 				sfp_get_info(sfp);
+				sfp_apply_quirks(sfp);
 				sds_config(machine.sfp_port[sfp].sds, sfp_rate_to_sds_config(rate));
 			}
 		} else {