Free meldware software for linux

Buni Meldware Communication Suite (MCS) is a platform-independent groupware package consisting of:
- Meldware Mail
- Meldware Calendar
- Meldware Webmail
- Meldware Secure Administration System
Together the package provides support for thousands of users concurrently to send and receive email and to schedule meetings. MCS uniquely allows you to store all messages and scheduling events in nearly any database and runs on nearly all popular software and hardware platforms.
MCS commitment to platform and database agnosticism aims to meet increasing business requirements to maximize ease and flexibility of managing and accessing data as well as putting a premium on interoperability.
Additionally, while the scheduling and calendaring services can be installed separately, the integrated feature set provides both a distinctive and powerful experience to both users and server-side Mail Based Applications and Collaboration Based Application Services.
The MCS platform provides security integration using LDAP sources including Microsoft Active Directory as well as flat-file and database sources.
Additionally, extensible security allows custom authentication/authorization sources.
Enhancements:
- This is the first milestone release with WCAP, freebusy for webmail, and mature IMAP all together.
- It has undergone extensive hardening, dogfooding, and QA testing.
- The WCAP protocol for calendaring now works well for Thunderbird and Lightning 0.3.
- Webmail calendaring was greatly improved.
- The abillity to download attachments has been added to the webmail interface.
- Numerous performance improvements have been made in SMTP, IMAP, and MIME parsing since 1.0-M7.