Disabling overriding of "default hanging build detection criteria" in a Job miscellaneous tab is ignored by Bamboo.

Steps to reproduce: (checked on 4.1.2 but I expect it still persist on 4.2++)

1) Create a plan with a Job.
2) edit Job's Miscellaneous configuration page
3) tick "Override default hanging build detection criteria"
4) note the "Build Queue Timeout" is empty (good! buildConfiguration for that job doesn't contain "custom.buildHangingConfig.minutesQueueTimeout" property as expected)
5) set "Build Queue Timeout" to something, i.e. "60". (Set the rest of fields so validation doesn't interfere)
6) save
7) note the "custom.buildHangingConfig.minutesQueueTimeout" property for that job will be set to "60" as expected
8) untick the "Override default hanging build detection criteria"
9) save
10a) the "custom.buildHangingConfig.minutesQueueTimeout" property will still be available in that job and will hold "60" as value - that's not expected
10b) instead I'd expect this property to be wiped out completely from configuration.
10c) if you tick the "Override default hanging build detection criteria" you will notice the "60" is still visible in the UI.