I Download the java software Here Installed the java Software i set the path in

My computers and right click and properties environment variables
here i add the

C:\Program Files\Java\jdk1.6.0_25\bin

After i came back to cmd prompt when i check the version it will shows the java1.6

After some times when i use eclipse and after i did the Couple of programs

again i checked the CMD prompt java -version

It will shows my version was 1.7

i again back to configuration in My computers and Checked .it will remains C:\Program Files\Java\jdk1.6.0_25\bin path only .wahy it happens like this Please share u r information..
iam using Windows XP