Update table on lost connection

[Alex Schaft]

Hi,

We're busy moving legacy apps from foxpro tables to mysql. User logins 
were tracked via a record in a table which the app then locked, 
preventing multiple logins for the same user code.

I want to simulate this via a "locked" column in a mysql table, but 
would need the field to be cleared if the server loses the connection to 
the client. How would I do this, or is there an alternative?

Thanks,
Alex