Pyramid run configurations with paster

I'm currently running a Vagrant box with Python 2.6.5 and pyramid 1.2.7. With this version of pyramid, I don't have pserve, so when I use the standard Pyramid run configuration, it fails because it doesn't exist, I require to use paster serve instead.

How do I go about changing the run arguments without having to update pyramid to a later version? I can't find pserve in the settings.

Thanks!