prayer binary package in Ubuntu Focal s390x

 Prayer is yet another Webmail interface.
 .
 It is unusual in that it is a complete, standalone, HTTP server and proxy
 rather a Apache/mod_php plugin. Prayer maintains persistent connections to
 the IMAP server and is written entirely in C. Consequently it is much
 faster than most open source Webmail interfaces and puts very little load
 on either the machines running the Web server or the backend IMAP servers
 (even if traditional Unix format mailfolders are in use).
 .
 Prayer has very few external dependencies as user preferences are stored on
 the IMAP server rather than in a SQL database. It does however implement a
 full range of features and user preference settings.

Source package