How to add a custom ant script to RTC build engine

I'm having trouble adding my custom ant script task to RTC build engine.
In RTC Eclipse Client, I created a plugin with a custom ant task class extending org.apache.tools.ant.Task. I exported the plugin into jar. I put the jar in RTC Eclipse Client dropins folder. I launched RTC Eclipse Client and could use the custom ant task without any issue.
However, I then tried to put the same jar into RTC build engine plugins directory. jazz\buildsystem\buildengine\eclipse\plugins.
Then I tried to access the custom task with RTC build engine. I consistently got an error message saying the task class can not be found.
2013-09-19 16:13:15 [Jazz build engine] running on host: TP-WENGT
2013-09-19 16:13:15 [Jazz build engine] Should build occur?
2013-09-19 16:13:15 [Jazz build engine] Yes: Always build a user initiated request.
2013-09-19 16:13:15 [Jazz build engine] Invoking build participant "com.ibm.team.build.ant"
Unable to locate tools.jar. Expected to find it in C:\Program Files (x86)\IBM\Java60\lib\tools.jar
Buildfile: C:\work\runtime-EclipseApplication\P1\anttask.xml
BUILD FAILED
C:\work\runtime-EclipseApplication\P1\anttask.xml:3: taskdef class <MY_CUSTOM_ANT_TASK_CLASS_NAME> cannot be found
Total time: 0 seconds
Build failed. Exit value was 1.
Comments
Marek Siekierski
Sep 20 '13, 12:03 p.m.Hi Tao,