Index: src/OFString.m
==================================================================
--- src/OFString.m
+++ src/OFString.m
@@ -865,11 +865,11 @@
 	       encoding: (of_string_encoding_t)encoding
 {
 	OFAutoreleasePool *pool;
 	OFHTTPRequest *request;
 	OFHTTPRequestResult *result;
-	OFMutableString *contentType;
+	OFString *contentType;
 	Class c;
 
 	c = isa;
 	[self release];
 
@@ -894,14 +894,13 @@
 			   HTTPRequest: request
 				result: result];
 
 	if (encoding == OF_STRING_ENCODING_AUTODETECT &&
 	    (contentType = [[result headers] objectForKey: @"Content-Type"])) {
-		contentType = [[contentType mutableCopy] autorelease];
-		[contentType lower];
+		contentType = [contentType lowercaseString];
 
-		if ([contentType hasSuffix: @"charset=UTF-8"])
+		if ([contentType hasSuffix: @"charset=utf-8"])
 			encoding = OF_STRING_ENCODING_UTF_8;
 		if ([contentType hasSuffix: @"charset=iso-8859-1"])
 			encoding = OF_STRING_ENCODING_ISO_8859_1;
 		if ([contentType hasSuffix: @"charset=iso-8859-15"])
 			encoding = OF_STRING_ENCODING_ISO_8859_15;