Last week I was tracking down an issue where I would get a PATH which looked
like this:

Path=C:\Windows\system32;...;"C:\Program Files\Java\jdk1.6.0_06\bin"

The problem is the quotes - they caused a batch file somewhere deep in the build
to break because the batch file (correctly!) quoted the %Path%.

I put tracing info all over the place, and it turned out that this was already
present at the time the slave was started via Java WebStart, so javaws must be
the culprit. If you launch it from a command prompt where the quotes are not
present, they are present by the time the slave starts up, and all goes to ****.

The workaround for us was to hack EnvVars to strip quotes from that variable
when it creates the initial one.