Index: wp-testcase/test_includes_formatting.php
===================================================================
--- wp-testcase/test_includes_formatting.php	(revision 481)
+++ wp-testcase/test_includes_formatting.php	(working copy)
@@ -357,6 +357,17 @@
 		$this->assertEquals($invalid_nest, wptexturize($invalid_nest));
 
 	}
+	
+	function test_escaped_quotes_17571() {
+		$this->knownWPBug(17571);
+		$this->assertEquals('“left half”', wptexturize('\"left half"'));
+		$this->assertEquals('“right half”', wptexturize('"right half\"'));
+		$this->assertEquals('“both”', wptexturize('\"both\"'));
+		$this->assertEquals('“neither”', wptexturize('"neither"'));
+		$this->assertEquals('“nested “both” quotes”', wptexturize('\"nested \"both\" quotes\"'));
+		$this->assertEquals("‘apostrophes, too’", wptexturize("'apostrophes, too'"));
+		$this->assertEquals("‘apostrophes and “escaped” quotes all together’", wptexturize("\'apostrophes and \"escaped\" quotes all together\'"));
+	}
 
 	//WP Ticket #1418
 	function test_bracketed_quotes_1418() {