diff --git a/NEWS b/NEWS
index 7fb9a4c2145..1d5c84ab2c9 100644
--- a/NEWS
+++ b/NEWS
@@ -5,6 +5,8 @@ PHP                                                                        NEWS
 - Optimized out a couple of per-request syscalls (Rasmus)
 - Optimized digest generation in md5() and sha1() functions. (Ilia)
 - Upgraded SQLite 3 to version 3.3.16 (Ilia)
+- Added a 4th parameter flag to htmlspecialchars() and htmlentities() that 
+  makes the function not encode existing html entities. (Ilia)
 - Added PDO::FETCH_KEY_PAIR mode that will fetch a 2 column result set into 
   an associated array. (Ilia)
 - Added function mysql_set_charset(). Allows connection encoding to be 
diff --git a/ext/standard/html.c b/ext/standard/html.c
index e2badee4748..8ac7b417c5f 100644
--- a/ext/standard/html.c
+++ b/ext/standard/html.c
@@ -1078,12 +1078,15 @@ empty_source:
 }
 /* }}} */
 
-
+PHPAPI char *php_escape_html_entities(unsigned char *old, int oldlen, int *newlen, int all, int quote_style, char *hint_charset TSRMLS_DC)
+{
+	return php_escape_html_entities_ex(old, oldlen, newlen, all, quote_style, hint_charset, 1 TSRMLS_CC);
+}
 
 
 /* {{{ php_escape_html_entities
  */
-PHPAPI char *php_escape_html_entities(unsigned char *old, int oldlen, int *newlen, int all, int quote_style, char *hint_charset TSRMLS_DC)
+PHPAPI char *php_escape_html_entities_ex(unsigned char *old, int oldlen, int *newlen, int all, int quote_style, char *hint_charset, zend_bool double_encode TSRMLS_DC)
 {
 	int i, j, maxlen, len;
 	char *replaced;
@@ -1145,8 +1148,34 @@ PHPAPI char *php_escape_html_entities(unsigned char *old, int oldlen, int *newle
 			int is_basic = 0;
 
 			if (this_char == '&') {
-				memcpy(replaced + len, "&", sizeof("&") - 1);
-				len += sizeof("&") - 1;
+				if (double_encode) {
+encode_amp:
+					memcpy(replaced + len, "&", sizeof("&") - 1);
+					len += sizeof("&") - 1;
+				} else {
+					char *e = memchr(old + i, ';', len - i);
+					char *s = old + i + 1;
+
+					if (!e || (e - s) > 10) { /* minor optimization to avoid "entities" over 10 chars in length */
+						goto encode_amp;
+					} else {
+						if (*s == '#') { /* numeric entities */
+							s++;
+							while (s < e) {
+								if (!isdigit(*s++)) {
+									goto encode_amp;
+								}
+							}
+						} else { /* text entities */
+							while (s < e) {
+								if (!isalnum(*s++)) {
+									goto encode_amp;
+								}
+							}
+						}
+						replaced[len++] = '&';
+					}
+				}
 				is_basic = 1;
 			} else {
 				for (j = 0; basic_entities[j].charcode != 0; j++) {
@@ -1193,12 +1222,13 @@ static void php_html_entities(INTERNAL_FUNCTION_PARAMETERS, int all)
 	int len;
 	long quote_style = ENT_COMPAT;
 	char *replaced;
+	zend_bool double_encode = 1;
 
-	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s|ls", &str, &str_len, &quote_style, &hint_charset, &hint_charset_len) == FAILURE) {
+	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s|lsb", &str, &str_len, &quote_style, &hint_charset, &hint_charset_len, &double_encode) == FAILURE) {
 		return;
 	}
 
-	replaced = php_escape_html_entities(str, str_len, &len, all, quote_style, hint_charset TSRMLS_CC);
+	replaced = php_escape_html_entities_ex(str, str_len, &len, all, quote_style, hint_charset, double_encode TSRMLS_CC);
 	RETVAL_STRINGL(replaced, len, 0);
 }
 /* }}} */
diff --git a/ext/standard/html.h b/ext/standard/html.h
index 3e896e18b5c..fec44bb0e45 100644
--- a/ext/standard/html.h
+++ b/ext/standard/html.h
@@ -38,6 +38,7 @@ PHP_FUNCTION(html_entity_decode);
 PHP_FUNCTION(get_html_translation_table);
 
 PHPAPI char *php_escape_html_entities(unsigned char *old, int oldlen, int *newlen, int all, int quote_style, char *hint_charset TSRMLS_DC);
+PHPAPI char *php_escape_html_entities_ex(unsigned char *old, int oldlen, int *newlen, int all, int quote_style, char *hint_charset, zend_bool double_encode TSRMLS_DC);
 PHPAPI char *php_unescape_html_entities(unsigned char *old, int oldlen, int *newlen, int all, int quote_style, char *hint_charset TSRMLS_DC);
 
 #endif /* HTML_H */
diff --git a/ext/standard/tests/strings/htmlentities18.phpt b/ext/standard/tests/strings/htmlentities18.phpt
new file mode 100644
index 00000000000..f171adaca2b
--- /dev/null
+++ b/ext/standard/tests/strings/htmlentities18.phpt
@@ -0,0 +1,31 @@
+--TEST--
+htmlentities() / htmlspecialchars() "don't double encode" flag support
+--FILE--
+<?php
+$tests = array(
+	"abc",
+	"abc&amp;sfdsa",
+	"test&#043;s &amp; some more &#68;",
+	"&; &amp &#a; &9;",
+	"&kffjadfdhsjfhjasdhffasdfas;",
+	"&#8787978789",
+);
+
+foreach ($tests as $test) {
+	var_dump(htmlentities($test, ENT_QUOTES, NULL, FALSE));
+	var_dump(htmlspecialchars($test, ENT_QUOTES, NULL, FALSE));
+}
+?>
+--EXPECT--
+string(3) "abc"
+string(3) "abc"
+string(13) "abc&amp;sfdsa"
+string(13) "abc&amp;sfdsa"
+string(33) "test&#043;s &amp; some more &#68;"
+string(33) "test&#043;s &amp; some more &#68;"
+string(20) "&; &amp;amp &#a; &9;"
+string(20) "&; &amp;amp &#a; &9;"
+string(32) "&amp;kffjadfdhsjfhjasdhffasdfas;"
+string(32) "&amp;kffjadfdhsjfhjasdhffasdfas;"
+string(16) "&amp;#8787978789"
+string(16) "&amp;#8787978789"