Upgrade from an earlier 1.9.x to 1.9.4+ (build 20090423) fails with the following message:

New version of eMail list (email_list) exists

Fatal error: Call to undefined function upgrade_block_savepoint() in /moodle/htdocs/moodleupgrade/blocks/email_list/db/upgrade.php on line 164

The correct upgrade library function name is upgrade_blocks_savepoint().