Ok friends i found a new trick.
If there is any zip file in your phone which containi .jar or .jad. And you are not able to extract them. Then download mini commander from the link Shriharsh.xtgem.com in java software section. Now after downloading it go to settings in mini commander and mark the option (make _jar or _jad to .jar or .jad) then extract the file in any folder. And rename the _jar file to .jar using your own phone.