Here is what I see in the altiris logs. It does appear the wake timer is set when the 7.5 agent is installed as I had a machine with 7.1 and it did not have it.
<event date='01/02/2014 18:04:01.5150000 -06:00' severity='4' hostName='R9T7H7C' source='ScheduleEngine' module='AgentScheduler.dll' process='AeXNSAgent.exe' pid='3388' thread='5836' tickCount='34339002' >
<![CDATA[Next event expected at 2014-01-03 00:00:00 -6:00, wakeup in 1 hour]]>
</event>
<event date='01/02/2014 18:04:01.5150000 -06:00' severity='4' hostName='R9T7H7C' source='ScheduleEngine' module='AgentScheduler.dll' process='AeXNSAgent.exe' pid='3388' thread='5836' tickCount='34339002' >
<![CDATA[Next event expected at 2014-01-03 00:00:00 -6:00, wakeup in 1 hour]]>
</event>
<event date='01/02/2014 18:04:01.5310000 -06:00' severity='4' hostName='R9T7H7C' source='ScheduleEngine' module='AgentScheduler.dll' process='AeXNSAgent.exe' pid='3388' thread='5832' tickCount='34339018' >
<![CDATA[A monitored event has occurred, check all schedules]]>