I just ran into the same and was able to fix it:
It appears that eclipse had copied over the preferences from my previous
workspace (I switched directly from 3.0.2 to 3.1M7) and did not adapt
certain pathes:
In Preferences => Ant => Runtime => Classpath tab I had to redefine the
Ant-Home to now point to "C:\eclipse\plugins\org.apache.ant_1.6.3" in my
case. it was still pointing to "C:\eclipse\plugins\org.apache.ant_1.6.2"
which was the location in 3.0.2, but which had disappeared with my
switch to 3.1M7. Maybe it's possible to use some classpath variable
here, to make this adaptation automagically, but this solved my problem
for now...
Hope that helps...
Michael
"Barry Kaplan" <groups1@xxxxxxxxxxx> wrote in message
news:d758i5$nv4$1@xxxxxxxxxxxxxxxxxxx
I just ran into the same Ant problem. I get a dialog:
title : "Java Virtual Machine Launcher"
message : "Could not find the main class. Program will exit."