You can configure an Oracle Workflow notification mailer with any cloud e-mail server that supports the SSL/TLS protocols, such as Office365 or Gmail. You can configure both outbound and inbound mailer processing. To do so, you must apply the cloud e-mail server support patch for your release. Patches are currently available for Oracle E-Business Suite Release 12.1.3
Refer below documents for further details
NOTE:2077434.1 - Configuring an Oracle Workflow Notification Mailer with Cloud E-Mail Servers
Right now we are in 12.1.2 (ATG 12.1.3) ,can I apply the cloud e-mail server support patches for only ATG 12.1.3
Is the only way to upgrade from 12.1.2 to 12.1.3 for SSL mail migration.
How do we find the version of mail.jar
version of mail.jar
Check the MANIFEST.MF file that is inside mail.jar (jar files are zip files containing a MANIFEST file under META-INF sub directory so you can use any zip file to look into it)