try to enter year 2039 in maintenance "Active till" area. it fails with message :
Maintenance "Active since" value cannot be bigger than "Active till".

the previous (and correct) message was :
"Active till" must be between 1970.01.01 and 2038.01.18

note that "Active till" fields are also cleared upon such error - they should stay the same user entered instead.

broken by :

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r29257 | pavels | 2012-07-31 16:36:29 +0300 (Tue, 31 Jul 2012) | 6 lines

A......... ZBX-5351 implemented the "selectTimeperiods" parameter for the maintenance.get method
A.F....... ZBX-5351 fixed an undefined index error when deleting maintenance time intervals
A.F....... ZBX-5351 fixed time intevals being recreated when updating maintenances
A.F....... ZBX-5351 corrected several maintenance API error messages
A......... ZBX-5351 removed excessive maintenance validation
A.F....... ZBX-5351 implemented the DB::replace() and DB::save() methods