Inline Mail Conversation Option

Currently in our configuration on PHPFox, all messages sent between members ad an individual message. It is not set up like most mail conversations where the each reply is within the same mail thread and the conversation history can be read by scrolling down. If you are having an ongoing conversation with someone this tends to make things difficult.

We have look high an low to find a setting that would allow a conversation to be within one message thread. We were not able to find one. Is there a setting in PHPFox that we are missing that allows for this? If not is anyone aware of an add on that would allow for this?

Thanks!