How can I pass values with spaces in them to the Execute Windows Batch command build step in Jenkins?

How can I pass values with spaces in them to the Execute Windows Batch
command build step in Jenkins?

My Setup: Mercurial DCVS (latest) and Jenkins CI (1.509.2) on an Amazon
EC2 Windows 2008 R2 instance.
I have a Jenkins build job that needs to create a VPN link between the
build server and our production server so that I can deploy the build
artifacts via FTP.
I'm attempting to use the Execute Windows Batch command build step to
execute a command similar to this:
rasdial NameOfConnection user@host.domain "password with spaces in it"
If I execute the command on the server in the console it works perfectly,
no problems at all. Executing in using the Execute Windows Batch command
build step fails completely. No amount of changing the quote type i.e.
double to single, or mixing and matching the pairs e.g. '"blah blah blah"'
has any effect.
... time passes ...
I've just tried moving the commands into a separate batch file
("ConnectNameOfConnectionVPN.bat") to be called from the Execute Windows
Batch command build step i.e. move, what appears to be an issue with
quotation marks outside of Jenkins. Unfortunately, this too seems to have
no impact, in fact I get the following error, which suggests that possibly
something else is going on.
Remote Access error 623 - The system could not find the phone book entry
for this connection.
At this point I don't know. I've seen the same error when executing the
commands directly from the Execute Windows Batch command build step.
Any help/hints graciously accepted.
Thanks