diff --git a/spring-test/src/main/java/org/springframework/mock/web/MockHttpServletRequest.java b/spring-test/src/main/java/org/springframework/mock/web/MockHttpServletRequest.java
index 40546ecb33..6c2873c4c0 100644
--- a/spring-test/src/main/java/org/springframework/mock/web/MockHttpServletRequest.java
+++ b/spring-test/src/main/java/org/springframework/mock/web/MockHttpServletRequest.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2015 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -50,6 +50,7 @@ import javax.servlet.http.HttpServletResponse;
 import javax.servlet.http.HttpSession;
 import javax.servlet.http.Part;
 
+import org.springframework.http.MediaType;
 import org.springframework.util.Assert;
 import org.springframework.util.LinkedCaseInsensitiveMap;
 import org.springframework.util.StringUtils;
@@ -368,9 +369,18 @@ public class MockHttpServletRequest implements HttpServletRequest {
 	public void setContentType(String contentType) {
 		this.contentType = contentType;
 		if (contentType != null) {
-			int charsetIndex = contentType.toLowerCase().indexOf(CHARSET_PREFIX);
-			if (charsetIndex != -1) {
-				this.characterEncoding = contentType.substring(charsetIndex + CHARSET_PREFIX.length());
+			try {
+				MediaType mediaType = MediaType.parseMediaType(contentType);
+				if (mediaType.getCharSet() != null) {
+					this.characterEncoding = mediaType.getCharSet().name();
+				}
+			}
+			catch (Exception ex) {
+				// Try to get charset value anyway
+				int charsetIndex = contentType.toLowerCase().indexOf(CHARSET_PREFIX);
+				if (charsetIndex != -1) {
+					this.characterEncoding = contentType.substring(charsetIndex + CHARSET_PREFIX.length());
+				}
 			}
 			updateContentTypeHeader();
 		}
diff --git a/spring-test/src/main/java/org/springframework/mock/web/MockHttpServletResponse.java b/spring-test/src/main/java/org/springframework/mock/web/MockHttpServletResponse.java
index 525197336a..ae42cb4c12 100644
--- a/spring-test/src/main/java/org/springframework/mock/web/MockHttpServletResponse.java
+++ b/spring-test/src/main/java/org/springframework/mock/web/MockHttpServletResponse.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2015 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -33,6 +33,7 @@ import javax.servlet.ServletOutputStream;
 import javax.servlet.http.Cookie;
 import javax.servlet.http.HttpServletResponse;
 
+import org.springframework.http.MediaType;
 import org.springframework.util.Assert;
 import org.springframework.util.LinkedCaseInsensitiveMap;
 import org.springframework.web.util.WebUtils;
@@ -216,10 +217,20 @@ public class MockHttpServletResponse implements HttpServletResponse {
 	public void setContentType(String contentType) {
 		this.contentType = contentType;
 		if (contentType != null) {
-			int charsetIndex = contentType.toLowerCase().indexOf(CHARSET_PREFIX);
-			if (charsetIndex != -1) {
-				this.characterEncoding = contentType.substring(charsetIndex + CHARSET_PREFIX.length());
-				this.charset = true;
+			try {
+				MediaType mediaType = MediaType.parseMediaType(contentType);
+				if (mediaType.getCharSet() != null) {
+					this.characterEncoding = mediaType.getCharSet().name();
+					this.charset = true;
+				}
+			}
+			catch (Exception ex) {
+				// Try to get charset value anyway
+				int charsetIndex = contentType.toLowerCase().indexOf(CHARSET_PREFIX);
+				if (charsetIndex != -1) {
+					this.characterEncoding = contentType.substring(charsetIndex + CHARSET_PREFIX.length());
+					this.charset = true;
+				}
 			}
 			updateContentTypeHeader();
 		}
diff --git a/spring-test/src/test/java/org/springframework/mock/web/MockHttpServletRequestTests.java b/spring-test/src/test/java/org/springframework/mock/web/MockHttpServletRequestTests.java
index 90f301a890..f0cd2866e6 100644
--- a/spring-test/src/test/java/org/springframework/mock/web/MockHttpServletRequestTests.java
+++ b/spring-test/src/test/java/org/springframework/mock/web/MockHttpServletRequestTests.java
@@ -100,6 +100,17 @@ public class MockHttpServletRequestTests {
 		assertEquals("UTF-8", request.getCharacterEncoding());
 	}
 
+	// SPR-12677
+
+	@Test
+	public void setContentTypeHeaderWithMoreComplexCharsetSyntax() {
+		String contentType = "test/plain;charset=\"utf-8\";foo=\"charset=bar\";foocharset=bar;foo=bar";
+		request.addHeader("Content-Type", contentType);
+		assertEquals(contentType, request.getContentType());
+		assertEquals(contentType, request.getHeader("Content-Type"));
+		assertEquals("UTF-8", request.getCharacterEncoding());
+	}
+
 	@Test
 	public void setContentTypeThenCharacterEncoding() {
 		request.setContentType("test/plain");
diff --git a/spring-test/src/test/java/org/springframework/mock/web/MockHttpServletResponseTests.java b/spring-test/src/test/java/org/springframework/mock/web/MockHttpServletResponseTests.java
index 0f1cbc8666..3ed21c536c 100644
--- a/spring-test/src/test/java/org/springframework/mock/web/MockHttpServletResponseTests.java
+++ b/spring-test/src/test/java/org/springframework/mock/web/MockHttpServletResponseTests.java
@@ -90,6 +90,23 @@ public class MockHttpServletResponseTests {
 		assertEquals("UTF-8", response.getCharacterEncoding());
 	}
 
+	// SPR-12677
+
+	@Test
+	public void contentTypeHeaderWithMoreComplexCharsetSyntax() {
+		String contentType = "test/plain;charset=\"utf-8\";foo=\"charset=bar\";foocharset=bar;foo=bar";
+		response.setHeader("Content-Type", contentType);
+		assertEquals(contentType, response.getContentType());
+		assertEquals(contentType, response.getHeader("Content-Type"));
+		assertEquals("UTF-8", response.getCharacterEncoding());
+
+		response = new MockHttpServletResponse();
+		response.addHeader("Content-Type", contentType);
+		assertEquals(contentType, response.getContentType());
+		assertEquals(contentType, response.getHeader("Content-Type"));
+		assertEquals("UTF-8", response.getCharacterEncoding());
+	}
+
 	@Test
 	public void setContentTypeThenCharacterEncoding() {
 		response.setContentType("test/plain");
diff --git a/spring-web/src/test/java/org/springframework/mock/web/test/MockHttpServletRequest.java b/spring-web/src/test/java/org/springframework/mock/web/test/MockHttpServletRequest.java
index 2df697d72c..144977e6e4 100644
--- a/spring-web/src/test/java/org/springframework/mock/web/test/MockHttpServletRequest.java
+++ b/spring-web/src/test/java/org/springframework/mock/web/test/MockHttpServletRequest.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2015 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -50,6 +50,7 @@ import javax.servlet.http.HttpServletResponse;
 import javax.servlet.http.HttpSession;
 import javax.servlet.http.Part;
 
+import org.springframework.http.MediaType;
 import org.springframework.util.Assert;
 import org.springframework.util.LinkedCaseInsensitiveMap;
 import org.springframework.util.LinkedMultiValueMap;
@@ -361,9 +362,18 @@ public class MockHttpServletRequest implements HttpServletRequest {
 	public void setContentType(String contentType) {
 		this.contentType = contentType;
 		if (contentType != null) {
-			int charsetIndex = contentType.toLowerCase().indexOf(CHARSET_PREFIX);
-			if (charsetIndex != -1) {
-				this.characterEncoding = contentType.substring(charsetIndex + CHARSET_PREFIX.length());
+			try {
+				MediaType mediaType = MediaType.parseMediaType(contentType);
+				if (mediaType.getCharSet() != null) {
+					this.characterEncoding = mediaType.getCharSet().name();
+				}
+			}
+			catch (Exception ex) {
+				// Try to get charset value anyway
+				int charsetIndex = contentType.toLowerCase().indexOf(CHARSET_PREFIX);
+				if (charsetIndex != -1) {
+					this.characterEncoding = contentType.substring(charsetIndex + CHARSET_PREFIX.length());
+				}
 			}
 			updateContentTypeHeader();
 		}
diff --git a/spring-web/src/test/java/org/springframework/mock/web/test/MockHttpServletResponse.java b/spring-web/src/test/java/org/springframework/mock/web/test/MockHttpServletResponse.java
index 080428883b..a1e7e243e1 100644
--- a/spring-web/src/test/java/org/springframework/mock/web/test/MockHttpServletResponse.java
+++ b/spring-web/src/test/java/org/springframework/mock/web/test/MockHttpServletResponse.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2015 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -33,6 +33,7 @@ import javax.servlet.ServletOutputStream;
 import javax.servlet.http.Cookie;
 import javax.servlet.http.HttpServletResponse;
 
+import org.springframework.http.MediaType;
 import org.springframework.util.Assert;
 import org.springframework.util.LinkedCaseInsensitiveMap;
 import org.springframework.web.util.WebUtils;
@@ -216,11 +217,20 @@ public class MockHttpServletResponse implements HttpServletResponse {
 	public void setContentType(String contentType) {
 		this.contentType = contentType;
 		if (contentType != null) {
-			int charsetIndex = contentType.toLowerCase().indexOf(CHARSET_PREFIX);
-			if (charsetIndex != -1) {
-				String encoding = contentType.substring(charsetIndex + CHARSET_PREFIX.length());
-				this.characterEncoding = encoding;
-				this.charset = true;
+			try {
+				MediaType mediaType = MediaType.parseMediaType(contentType);
+				if (mediaType.getCharSet() != null) {
+					this.characterEncoding = mediaType.getCharSet().name();
+					this.charset = true;
+				}
+			}
+			catch (Exception ex) {
+				// Try to get charset value anyway
+				int charsetIndex = contentType.toLowerCase().indexOf(CHARSET_PREFIX);
+				if (charsetIndex != -1) {
+					this.characterEncoding = contentType.substring(charsetIndex + CHARSET_PREFIX.length());
+					this.charset = true;
+				}
 			}
 			updateContentTypeHeader();
 		}