I was in two minds about putting that text in.  I took the perspective of an end-user (devops/sysadmin);

1. The sysadmin puts the service into a paused state
2. The event log says "Service Pausing"
3. After some time the service starts running again
4. Sysadmin is confused because if something's paused it should stay that way until it's resumed

What would the Sysadmin then do?
* Search for errors like this
* Raise an issue with PuppetLabs
* Read the source code

This isn't a good experience for the end-user because it is contrary to the expected behaviour of putting a service into a Paused state.  
Whether or not the behaviour is intentional by PuppetLabs or a dependency of Puppet is, to me, mostly irrelevant to the end-user.  By being more verbose in the message that is logged, the end-user now knows what behvaiour to expect.

Perhaps changing the message to be more friendly could be a better solution? e.g.
"Service pausing. The service will not stay paused. See Puppet Issue xxxx for more information."