This appears to be a wrong check if the package is installed or not when the version is set with a numeric version.
I've tried with few differents packages, here is the example with emacs.
When I try this:
10.34.xxx.xxx> -> info: Successfully installed package 'emacs'
But when I try with a specific version like this :
Jun 15 10:55:20 XXXXXXX : CFEngine(agent) Error installing package 'emacs'
But the fact is that package is actually well installed with the right version.