Mangesieve security question

Hello,

I have a dovecot 2.2.6 on a Linux platform. I have configured manageseive extension.

I have opened the manageseive port (4190) to entire world. (since I need my thunderbird and other clients to create seive scripts).

I just wanted to know if it is ok to open that port to everyone, and get some feedback on some security measures specific to manageseive.

-Thanks in advance Vijay

PS: I have taken reasonable server hardening measures. This question is specific to manageseive.