Your results contain 13 solutions with the following criteria :

Messaging, Email Marketing & Groupware
Solution Smile rating Users rating Popularity
Zimbra Zimbra 4.5 Smile 3.6 Visitors
100%   Popularity on the site
Zarafa Zarafa 3.8 Smile No rating
69%   Popularity on the site
SpamAssassin SpamAssassin 3.8 Smile No rating
26%   Popularity on the site
RoundCube No rating No rating
38%   Popularity on the site
postfix Postfix 4.3 Smile No rating
40%   Popularity on the site
OpenEMM OpenEMM 2.7 Smile No rating
48%   Popularity on the site
Open-Xchange No rating No rating
44%   Popularity on the site
OBM logo OBM No rating No rating
34%   Popularity on the site
Horde Horde 3.3 Smile No rating
46%   Popularity on the site
EGroupware No rating 1.8 Visitors
39%   Popularity on the site