Index: src/OFXMLAttribute.h
==================================================================
--- src/OFXMLAttribute.h
+++ src/OFXMLAttribute.h
@@ -30,10 +30,11 @@
 {
 #if defined(OF_XML_ELEMENT_M) || defined(OF_XML_PARSER_M)
 @public
 #endif
 	OFString *_name, *_Nullable _namespace, *_stringValue;
+	bool _useDoubleQuotes;
 }
 
 /*!
  * @brief The name of the attribute.
  */

Index: src/OFXMLElement.m
==================================================================
--- src/OFXMLElement.m
+++ src/OFXMLElement.m
@@ -523,22 +523,26 @@
 	}
 
 	/* Attributes */
 	for (OFXMLAttribute *attribute in _attributes) {
 		void *pool2 = objc_autoreleasePoolPush();
-		OFString *attributeName = [attribute name];
+		const char *attributeNameCString =
+		    [attribute->_name UTF8String];
+		size_t attributeNameLength =
+		    [attribute->_name UTF8StringLength];
 		OFString *attributePrefix = nil;
 		OFString *tmp = [[attribute stringValue] stringByXMLEscaping];
+		char delimiter = (attribute->_useDoubleQuotes ? '"' : '\'');
 
-		if ([attribute namespace] != nil &&
+		if (attribute->_namespace != nil &&
 		    (attributePrefix = [allNamespaces objectForKey:
-		    [attribute namespace]]) == nil)
+		    attribute->_namespace]) == nil)
 			@throw [OFUnboundNamespaceException
 			    exceptionWithNamespace: [attribute namespace]
 					   element: self];
 
-		length += [attributeName UTF8StringLength] +
+		length += attributeNameLength +
 		    (attributePrefix != nil ?
 		    [attributePrefix UTF8StringLength] + 1 : 0) +
 		    [tmp UTF8StringLength] + 4;
 
 		@try {
@@ -554,18 +558,17 @@
 			memcpy(cString + i, [attributePrefix UTF8String],
 			    [attributePrefix UTF8StringLength]);
 			i += [attributePrefix UTF8StringLength];
 			cString[i++] = ':';
 		}
-		memcpy(cString + i, [attributeName UTF8String],
-		    [attributeName UTF8StringLength]);
-		i += [attributeName UTF8StringLength];
+		memcpy(cString + i, attributeNameCString, attributeNameLength);
+		i += attributeNameLength;
 		cString[i++] = '=';
-		cString[i++] = '\'';
+		cString[i++] = delimiter;
 		memcpy(cString + i, [tmp UTF8String], [tmp UTF8StringLength]);
 		i += [tmp UTF8StringLength];
-		cString[i++] = '\'';
+		cString[i++] = delimiter;
 
 		objc_autoreleasePoolPop(pool2);
 	}
 
 	/* Children */

Index: src/OFXMLParser.m
==================================================================
--- src/OFXMLParser.m
+++ src/OFXMLParser.m
@@ -840,10 +840,11 @@
 - (void)of_inAttributeValueState
 {
 	void *pool;
 	OFString *attributeValue;
 	size_t length;
+	OFXMLAttribute *attribute;
 
 	if (_data[_i] != _delimiter)
 		return;
 
 	if ((length = _i - _last) > 0)
@@ -857,14 +858,15 @@
 					     forKey: @""];
 	if ([_attributePrefix isEqual: @"xmlns"])
 		[[_namespaces lastObject] setObject: attributeValue
 					     forKey: _attributeName];
 
-	[_attributes addObject:
-	    [OFXMLAttribute attributeWithName: _attributeName
-				    namespace: _attributePrefix
-				  stringValue: attributeValue]];
+	attribute = [OFXMLAttribute attributeWithName: _attributeName
+					    namespace: _attributePrefix
+					  stringValue: attributeValue];
+	attribute->_useDoubleQuotes = (_delimiter == '"');
+	[_attributes addObject: attribute];
 
 	objc_autoreleasePoolPop(pool);
 
 	[_buffer removeAllItems];
 	[_attributeName release];