This is more a MySQL bug, but since it is an SMF supported version of MySQL, we might want to at the very least handle it more gracefully.
Certain versions of MySQL 5.0.x have a bug where they will return a hard error when certain system variables are SELECTed.
More info on the MySQL bug here:
https://bugs.mysql.com/bug.php?id=15684
We query version_comments, one of the impacted variables, in smf_db_get_engine().
Two SMF 2.0.15+ support cases here:
https://www.simplemachines.org/community/index.php?topic=557279.0
https://www.simplemachines.org/community/index.php?topic=557246.0
We may want to consider handling this error more gracefully.
Note that I believe the ONLY functions impacted are the 'Administration Center' and 'Support and Credits'. Which don't really do anything, so users can work around this pretty easily.
Hope this makes sense. Any questions, let me know.
There's even precedent for this - look for the MySQL 5.0.51-52 patch.
Possible fix for smf 2.1(would work in 2.0.x also) is in place: https://github.com/SimpleMachines/SMF2.1/pull/4391
Looks like it should do it, yes.