TYPO3 Core

for 4.5/4.7 this is in: t3lib/stddb/tbl_pages.php

It didn't occur to me on regular installations, so I wonder if maybe newer MySQL-releases are a bit more picky about trying to set an empty string for a integer-column. But it's wrong with trying to set a string there anyhow ...
Happened to me locally with Fedora 19 using mariadb-server-5.5.32-8.fc19

Turns out that from recent system-environment-testing I still had "sql-mode = STRICT_ALL_TABLES" in my.cnf. Removing that makes the problem go away. Still fix it since it's "wrong"?

Any chance to reconsider this decision for older version? It's no help for current (even LTS) users to keep this bug around. MySQL, and MariaDB are configured in strict mode by default.

An alternative solution would be to be able to set the SQL_MODE for the session from within Typo3 -- it may not always be possible to influence the global SQL_MODE that is used on hosting solutions.

Hmm, default on your hosting-environment or really a MySQL-default? Do you know since what versions?

Strict mode is a MySQL default on Windows at least since version 5.0.

Strict mode is also the default on Mac when using the current MySQL installer packages (mysql-5.6.17-osx10.7-x86_64.dmg).