Java compilation issue with Eclipse settings

Today I got an interesting error while running my sample java appliaction. Error is
Access restriction: The method createJPEGEncoder(OutputStream) from the type JPEGCodec is not accessible due to
restriction on required library C:\Program Files\Java\jdk1.6.0_11\jre\lib\rt.jar

Access restriction: The method getDefaultJPEGEncodeParam(BufferedImage) from the type JPEGImageEncoder is not accessible due to
restriction on required library C:\Program Files\Java\jdk1.6.0_11\jre\lib\rt.jar

Access restriction: The method setJPEGEncodeParam(JPEGEncodeParam) from the type JPEGImageEncoder is not accessible due to
restriction on required library C:\Program Files\Java\jdk1.6.0_11\jre\lib\rt.jar ImageUtil.java.

One of my java application program importing Sun default package "com.sun.image.codec.jpeg.JPEGCodec" which is in C:\Program Files\Java\jdk1.6.0_11\jre\lib\rt.jar.
Upto yesterday its worked for me without any issues except some warning messages, Suddenly today I am unable to run the application and getting above error.
A quick googling Its resolved with small setting modification in eclipse.

Solution :
1. Go to Project properties
2. Expand Java Compiler and Click on Errors/Warnings
3. Click Enable project specific settings.
4. Expand Depricated and restricted API
5. Change forbidden reference(access rules) setting as warning or ignore.

Now try to run the java application.