Jenkins seems to clean the default <remote_fs_root>/workspace/.. directory every 24 hours! As a result the job workspace that is tied to a p4 plugin and does not 'let jenkins manage workspace view' gets deleted periodically. These jobs also define a custom job workspace directory under the advanced project config options.
There were similar issues reported before and they seem to have been resolved. But I guess, such a case where Jenkins doesn't manage the custom p4 workspace were not considered and hence I'm putting it up again.

The log states..
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Mar 10, 2011 7:15:42 PM hudson.model.AsyncPeriodicWork$1 run
INFO: Started Workspace clean-up
Mar 10, 2011 7:16:32 PM hudson.model.AsyncPeriodicWork$1 run
INFO: Finished Workspace clean-up. 50544 ms
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