Cannot register users on custom Jabber server

[serenewaffles]

I am able to successfully register a user on my Jabber server using Pidgin. However, when I attempt to do the same using ChatSecure, I get an error:

"error creating account unable to connect to host"

The device attempting to create the account and receiving the above error is at the same time connected to the Jabber server in question (and able to chat with other users) using a different account.

Happy to provide devs information regarding my server, but would prefer to not post addresses publicly.