I don't feel the above comments are based on fact, but rather sound like someone trying to hinder the growth of Perl (mod_perl) or someone that is bitter about their experience with mod_perl.
But in case this node is visited in the future, let me add my 2 cents to the pot.
All the pieces exist for a Zend/Tomcat type "packaging" of mod_perl, but there are many entrenched users of mod_perl that don't have time to switch to a new methods. One of the reasons being that mod_perl predates (I believe) the other solutions mentioned
mod_perl is a full open source project which is not directly funded by an organization earning its revenue directly from its sales (use), unlike the two examples you provide. Therefore mod_perl is community/need driven rather then "packaging" driven.
merlyn has talked about writing an aricle/guide/whatever on how to setup Template Toolkit 2
in a mod_perl environment to replace php. Since
users aren't writing perl directly, the potential for users mucking up other users programs goes down ... it's not a bad idea (for ISPs or anyone who can't run a server per user...).
As to your troll comments, I don't think it's a troll (but I do think it may be somebody trying to persuade merlyn to write this already in a somewhat subtle manner).
MJDsays "you can't just make shit up and expect the computer to know what you mean, retardo!"