Problems with variables since upgrader to 3.8.5
 

We have been using 3.7.2 for some time now on live forums and in order to bring the forums up to the latest software, I have been testing upgrading the forums offline to 3.8.5. Everything seemed to work fine from the point of view of the templates, style sheets and general appearance but one thing that has become apparent is that where we were using variables in various phrases in the forum e.g. confirmation of registration, emails to acknowledge registration, they now just get displayed as their variable form e.g. $username or $email and not as the actual substituted data that should appear ie the username for the particular registrant or their email address.

I can't find anywhere where the variables are listed or even where there might be a reference dictionary of what might work in the software. Is anyone aware of code changes that would have stopped these working 3.7.2 to 3.8.5 and does anyone have an idea of how to solve the issue?

Rob