No Command Prompt after Login w/Sieveshell (Cyrus IMAPd 2.3.13)

[Jorey Bump]

This is the first time I've used sieveshell since upgrading to Cyrus
IMAPd 2.3.13. It will prompt me for my password, but once I log in, it
simply hangs without any feedback or providing a '>' command prompt.
According to the log, login was successful:

 sieve[29093]: login: localhost[127.0.0.1] jorey DIGEST-MD5 User logged in

There are no other related entries that follow, other than the
disconnection message when I hit Ctrl-C to abort. I've used previous
versions of sieveshell successfully, but I'm getting the same behaviour
on two different installations of Cyrus IMAPd 2.3.13.

I really need to get this vacation message installed today. Is there a
known fix? If not, is there a way to install the script manually,
bypassing sieveshell?