As far as I know, mySQL does not have the concept of "jobs." Processing of this type is usually done by, say, shell-scripts (in Python, Perl, or what-have-you) that are external to MySQL.
I believe that the system messages are stored in an external file for nationalization purposes but once again I do not believe that you can "personalize" them.
Remember: if a particular product doesn't provide an important feature you need, there are others and the correct decision is usually, "use another!" Don't be dissuaded by the presence of license-fees but of course factor them into your decision. Your time's worth money too... big money. Identify the technical requirements of your application and choose the one that fits best. Some amount of shoehorning will be needed to make any pair of shoes "fit." Each possible alternative will present a different set of technical compromises vis a visyour intended application.