OK ... found something interesting in the MySQL Server logs ...
2013-05-14 13:53:18.84 spid1s Server resumed execution after being idle 228 seconds. Reason: timer event.
2013-05-14 15:27:19.16 spid51 Starting up database 'Account'.
2013-05-14 15:27:24.45 spid51 Recovery completed for database Account (database ID 5) in 1 second(s) (analysis 388 ms, redo 0 ms, undo 344 ms.) This is an informational message only. No user action is required.
2013-05-14 15:33:11.61 Logon Error: 18456, Severity: 14, State: 38.
2013-05-14 15:33:11.61 Logon Login failed for user 'sa'. Reason: Failed to open the explicitly specified database. [CLIENT: 192.168.0.253]
2013-05-14 15:34:00.80 Logon Error: 18456, Severity: 14, State: 38.
2013-05-14 15:34:00.80 Logon Login failed for user 'sa'. Reason: Failed to open the explicitly specified database. [CLIENT: 192.168.0.253]
2013-05-14 15:35:37.09 spid53 Starting up database 'Server01'.
2013-05-14 15:56:34.90 Logon Error: 18456, Severity: 14, State: 38.
2013-05-14 15:56:34.90 Logon Login failed for user 'sa'. Reason: Failed to open the explicitly specified database. [CLIENT: 192.168.0.251]
2013-05-14 15:59:52.53 spid51 Starting up database 'EventData'.
2013-05-14 16:02:08.68 Logon Error: 18456, Severity: 14, State: 38.
2013-05-14 16:02:08.68 Logon Login failed for user 'sa'. Reason: Failed to open the explicitly specified database. [CLIENT: 192.168.0.251]
2013-05-14 16:02:54.38 Logon Error: 18456, Severity: 14, State: 38.
2013-05-14 16:02:54.38 Logon Login failed for user 'sa'. Reason: Failed to open the explicitly specified database. [CLIENT: 192.168.0.251]
2013-05-14 16:19:35.98 Logon Error: 18456, Severity: 14, State: 38.
2013-05-14 16:19:35.98 Logon Login failed for user 'sa'. Reason: Failed to open the explicitly specified database. [CLIENT: 192.168.0.251]
2013-05-14 16:26:12.48 Logon Error: 18456, Severity: 14, State: 38.
2013-05-14 16:26:12.48 Logon Login failed for user 'sa'. Reason: Failed to open the explicitly specified database. [CLIENT: 192.168.0.251]
2013-05-14 16:49:31.54 Logon Error: 18456, Severity: 14, State: 38.
2013-05-14 16:49:31.54 Logon Login failed for user 'sa'. Reason: Failed to open the explicitly specified database. [CLIENT: 192.168.0.251]
2013-05-14 16:52:21.08 Logon Error: 18456, Severity: 14, State: 38.
2013-05-14 16:52:21.08 Logon Login failed for user 'sa'. Reason: Failed to open the explicitly specified database. [CLIENT: 192.168.0.251]
2013-05-14 18:29:00.26 Logon Error: 18456, Severity: 14, State: 38.
2013-05-14 18:29:00.26 Logon Login failed for user 'sa'. Reason: Failed to open the explicitly specified database. [CLIENT: 192.168.0.251]
2013-05-14 18:48:19.01 Logon Error: 18456, Severity: 14, State: 38.
2013-05-14 18:48:19.01 Logon Login failed for user 'sa'. Reason: Failed to open the explicitly specified database. [CLIENT: 192.168.0.251]
This seems to be a big problem ...