Mono 22.214.171.124 is a minor bug fix release on the Mono 1.1.8.x series, for more details on 1.1.8 see its release notes.
See also the release notes for Mono 126.96.36.199
Fixed deadlocks when running heavily multi-threaded applications in debug mode (--debug) (Ben).
Implements the various security and validations modes in forms authentication (system.web/machineKey section). This is an important upgrade for ASP.NET users.
Source code and packages are available from: http://www.mono-project.com/Downloads