XenForo 1.2.4 is a maintenance release in the 1.2 series and focuses on bug fixes and stability improvements. We recommend that all customers running a previous version of 1.2 upgrade when possible. If you are currently running XenForo 1.0 or 1.1, we also recommend upgrading to 1.2 when possible, but please be aware that this is a significant upgrade and you'll need to be aware of add-on and style compatibility changes.
The bugs fixed in this release include:
Generate message IDs when sending mail
Fix an issue where not all characters were escaped for quoted printable encoding of email headers
Improved random number generation with additional sources and enhanced entropy
Add support for forcing a character set when importing from IPB...