Bugfixes and improvements on address book (pagination), sendmail (see below) and sharding.
Sendmail translates a single line with a dot as an interruption command. If you are using this mailer, make sure to either configure it to ignore this configuration (see IgnoreDots). It is better to pass this as a static configuration, but it can also be done using runtime parameters. You can set them directly in Cells configuration file under the "defaults/sendmailParams" key (must be an array of strings).
For example, binary path and custom parameters can be set as follow :
{
  "defaults":{
    "sendmail":"/usr/sbin/sendmail",
    "sendmailParams":["-i"],
  "..."
  },
  "..."
}
Upgrade is recommended. See Cells 2.2 release note for details about major release features.