It is highly recommended to regularly change your password, both on the server and on the forums!
There may be a leaked database circulating again - however the database was used on an old iteration of the script, and it was sold several years ago by a former owner/developer. (Algren)
The database contains old and hopefully outdated passwords, however if you did not change password in the last 5 years, you might be at risk.
It has been confirmed by one affected community member that he did not change password, which leads me to believe my thesis is correct.
Again; Avoid using the same passwords on copied IM servers, or other communities that may or may not be 100% serious/secure. Don't use the same password for the server and the forum.
Use unique passwords as many places as possible and do not use your e-mail account's password on gaming sites.