Index: t3lib/class.t3lib_htmlmail.php
===================================================================
--- t3lib/class.t3lib_htmlmail.php	(revision 3639)
+++ t3lib/class.t3lib_htmlmail.php	(working copy)
@@ -476,7 +476,7 @@
 
 			// From
 		if ($this->from_email) {
-			if ($this->from_name) {
+			if ($this->from_name && !t3lib_div::isBrokenEmailEnv()) {
 				$this->add_header('From: '.$this->from_name.' <'.$this->from_email.'>');
 			} else {
 				$this->add_header('From: '.$this->from_email);
@@ -708,35 +708,38 @@
 
 			// On windows the -f flag is not used (specific for Sendmail and Postfix),
 			// but instead the php.ini parameter sendmail_from is used.
-		$returnPath = (strlen($this->returnPath) > 0) ? '-f'.$this->returnPath : '';
+		$returnPath = (strlen($this->returnPath) > 0) ? '-f "' . addslashes($this->returnPath) . '"' : '';
 		if($this->returnPath) {
-			ini_set(sendmail_from, $this->returnPath);
+			ini_set('sendmail_from', t3lib_div::adjustMailAddressForEnv($this->returnPath));
 		}
+		$recipient = t3lib_div::adjustMailAddressForEnv($this->recipient);
+		$recipient_copy = t3lib_div::adjustMailAddressForEnv($this->recipient_copy);
+
 		// If safe mode is on, the fifth parameter to mail is not allowed, so the fix wont work on unix with safe_mode=On
 		$returnPathPossible = (!ini_get('safe_mode') && $this->forceReturnPath);
 		if ($returnPathPossible) {
-			$mailWasSent = mail($this->recipient,
+			$mailWasSent = mail($recipient,
 				  $this->subject,
 				  $this->message,
 				  $this->headers,
 				  $returnPath);
 		} else {
-			$mailWasSent = mail($this->recipient,
+			$mailWasSent = mail($recipient,
 				  $this->subject,
 				  $this->message,
 				  $this->headers);
 		}
 
 			// Sending a copy
-		if ($this->recipient_copy) {
+		if ($recipient_copy) {
 			if ($returnPathPossible) {
-				$mailWasSent = mail($this->recipient_copy,
+				$mailWasSent = mail($recipient_copy,
 					$this->subject,
 					$this->message,
 					$this->headers,
 					$returnPath);
 			} else {
-				$mailWasSent = mail($this->recipient_copy,
+				$mailWasSent = mail($recipient_copy,
 					$this->subject,
 					$this->message,
 					$this->headers);
@@ -750,17 +753,17 @@
 				$mailWasSent = mail($this->from_email,
 					$theParts[0],
 					$theParts[1],
-					"From: ".$this->recipient,
+					'From: ' . $recipient,
 					$returnPath);
 			} else {
 				$mailWasSent = mail($this->from_email,
 					$theParts[0],
 					$theParts[1],
-					"From: ".$this->recipient);
+					'From: ' . $recipient);
 			}
 		}
 		if ($this->returnPath) {
-			ini_restore(sendmail_from);
+			ini_restore('sendmail_from');
 		}
 		return $mailWasSent;
 	}
Index: t3lib/class.t3lib_div.php
===================================================================
--- t3lib/class.t3lib_div.php	(revision 3639)
+++ t3lib/class.t3lib_div.php	(working copy)
@@ -1427,6 +1427,37 @@
 	}
 
 	/**
+	 * Checks if current e-mail sending method does not accept recipient/sender name
+	 * in a call to PHP mail() function. Windows version of mail() and mini_sendmail
+	 * program are known not to process such input correctly and they cause SMTP
+	 * errors. This function will return true if current mail sending method has
+	 * problem with recipient name in recipient/sender argument for mail().
+	 *
+	 * TODO: 4.3 should have additional configuration variable, which is combined
+	 * by || with the rest in this function.
+	 *
+	 * @return	boolean	true if mail() does not accept recipient name
+	 */
+	public static function isBrokenEmailEnv() {
+		return TYPO3_OS == 'WIN' || (false !== strpos(ini_get('sendmail_path'), 'mini_sendmail'));
+	}
+
+	/**
+	 * Changes from/to arguments for mail() function to work in any environment.
+	 *
+	 * @param	string	$address	Address to adjust
+	 * @return	string	Adjusted address
+	 * @see	t3lib_::isBrokenEmailEnv()
+	 */
+	public static function adjustMailAddressForEnv($address) {
+		if (self::isBrokenEmailEnv() && false !== ($pos1 = strrpos($address, '<'))) {
+			$pos2 = strpos($address, '>', $pos1);
+			$address = substr($address, $pos1 + 1, ($pos2 ? $pos2 : strlen($address)) - $pos1 - 1);
+		}
+		return $address;
+	}
+
+	/**
 	 * Formats a string for output between <textarea>-tags
 	 * All content outputted in a textarea form should be passed through this function
 	 * Not only is the content htmlspecialchar'ed on output but there is also a single newline added in the top. The newline is necessary because browsers will ignore the first newline after <textarea> if that is the first character. Therefore better set it!
@@ -4634,12 +4665,16 @@
 			$charset = $GLOBALS['TYPO3_CONF_VARS']['BE']['forceCharset'] ? $GLOBALS['TYPO3_CONF_VARS']['BE']['forceCharset'] : 'ISO-8859-1';
 		}
 
+		$email = self::adjustMailAddressForEnv($email);
 		if (!$dontEncodeHeader)	{
 				// Mail headers must be ASCII, therefore we convert the whole header to either base64 or quoted_printable
 			$newHeaders=array();
 			foreach (explode(chr(10),$headers) as $line)	{	// Split the header in lines and convert each line separately
 				$parts = explode(': ',$line,2);	// Field tags must not be encoded
 				if (count($parts)==2)	{
+					if (0 == strcasecmp($parts[0], 'from')) {
+						$parts[1] = self::adjustMailAddressForEnv($parts[1]);
+					}
 					$parts[1] = t3lib_div::encodeHeader($parts[1],$encoding,$charset);
 					$newHeaders[] = implode(': ',$parts);
 				} else {
@@ -4679,14 +4714,12 @@
 			break;
 		}
 
-		$linebreak = chr(10);			// Default line break for Unix systems.
-		if (TYPO3_OS=='WIN')	{
-			$linebreak = chr(13).chr(10);	// Line break for Windows. This is needed because PHP on Windows systems send mails via SMTP instead of using sendmail, and thus the linebreak needs to be \r\n.
-		}
+		// Headers must be separated by CRLF according to RFC 2822, not just LF.
+		// But many servers (Gmail, for example) behave incorectly and want only LF.
+		// So we stick to LF in all cases.
+		$headers = trim(implode(chr(10), t3lib_div::trimExplode(chr(10), $headers, true)));	// Make sure no empty lines are there.
 
-		$headers=trim(implode($linebreak,t3lib_div::trimExplode(chr(10),$headers,1)));	// Make sure no empty lines are there.
-
-		$ret = @mail($email,$subject,$message,$headers);
+		$ret = @mail($email, $subject, $message, $headers);
 		if (!$ret)	{
 			t3lib_div::sysLog('Mail to "'.$email.'" could not be sent (Subject: "'.$subject.'").', 'Core', 3);
 		}