[Mimedefang] Mysql connections

[Mack]

>If you put a dbh->prepare statement immediately before each execute(), it
should work...bearing in mind that I >haven't been able to test this.

Only advantage gained here is the persistant connection, as the prep
statements (or prep_cached) seem to have their own large overheads..

My guess is it's a problem in the 3rd party interfaces (as PhP has the same
issue with pconnect and MSSQL !)

I gave up in the end and ensured that at the start of each sub a connect_DB
call is made and a release_DB at the end, and tbh the overhead is livable
with - can still process 100k+ msgs a day