taskdef class ...CleanImports cannot be found

[lvup]

I just setup Ant on my machine. I tried running ant clean dist and this is the error I see:

taskdef class com.tombrus.cleanImports.ant.CleanImports cannot be found

I have set the following Environmental variables:
PATH: .;C:\Program Files\jdev1012\jdk\bin;C:\Program Files\apache-ant-1.6.5\bin
ANT_HOME: C:\Program Files\apache-ant-1.6.5
JAVA_HOME: C:\Program Files\jdev1012\jdk

I am using the following version of ant:
Apache Ant version 1.6.5 compiled on June 2 2005

Please let me know how to fix this issue
Thanks!