[SalesForce] bug in milestones elapsed time

We noticed recently that the "elapsed time" of a milestone does not seem to exclude the time that the entitlement process was stopped.
To us, that's a clear bug but I would like to know if other people have also seen this behavior and what their solution was to have the correct elapsed time.

First test: impact of stopping the clock on the "Elapsed Time"

Milestone start date:       25/02/2015 09:34
Target response time:       10 mins
Target Date                 25/02/2015 09:44
Stopped Since:              25/02/2015 09:35
Restarted at:               25/02/2015 09:47
Completed milestone at:     25/02/2015 09:47
Elapsed time after close:   13 mins
Violation                   NOT CHECKED! (although the elapsed time is greater than the target response time...)
Target Date                 25/02/2015 09:56 (moved by the time process was stopped)

so, the clock being stopped or not does not influence the elapsed time while it should… Also, as long as the milestone is not yet completed, you have the "time remaining" which IS being influenced by the entitlement being stopped or not

Second test (as a sanity check… you would start doubting everything): impact of the business hours on the "Elapsed Time"

Case opened outside of business hours
business hours of day of testing: 10:00 to 10:05 AM

Start Date                  25/02/2015 09:54 AM
Target Date                 26/02/2015 00:55 AM
Target Response (Mins)      60
Completion milestone at:    25/02/2015 10:06
Elapsed time:               5 mins

so here, the business hours DO have impact on the elapsed time

could someone confirm this buggy behavior please and let me know if there are workarounds?