JAVA_HOME defined but maven2 compains it could not find it

[Tapas Mishra]

/usr/lib/jvm/java-6-sun-1.6.0.20/bin
is the directory where my Java resides.
in the .bashrc have following


JAVA_HOME="/usr/lib/jvm/java-6-sun-1.6.0.20/bin"
export JAVA_HOME

/etc/environment and /etc/profile
have the default entries no changes with them.


 echo $JAVA_HOME
/usr/lib/jvm/java-6-sun-1.6.0.20/bin

then Installed


aptitude install maven2

when I run mvn get error


Error: JAVA_HOME is not defined correctly.
  We cannot execute /usr/lib/jvm/java-6-sun-1.6.0.20/bin/bin/java

I am not having any clue as what is this error?
As to me JAVA_HOME seems to be defined.