strange entries in /var/log/messages

["Adv. Systems Design" <asd_2000 yahoo com>]

I keep getting these in /var/log/messages and can't
figure out whats causing it (3 every hour, every day)

Jan  7 11:15:58 mecha -- MARK --
Jan  7 11:35:58 mecha -- MARK --
Jan  7 11:55:58 mecha -- MARK --
Jan  7 12:15:58 mecha -- MARK --
Jan  7 12:35:58 mecha -- MARK --
Jan  7 12:55:58 mecha -- MARK --

Any ideas are welcome...
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