Sharepoint Delay Activity Timer
Sharepoint Delay Activity is rounded off to the minute interval that is setup for 'job-workflow' property. This is because the job is responsible for waking up the workflow at the specified time. This job is usually set to run every 5 minutes.
It is easy to change (increase or decrease) this value.
To get the current job interval value:
C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\BIN\stsadm -o getproperty -pn job-workflow -url http://siteaddress
Or to change it every minute