Then go to the following web address: https://ssl.sentex.ca/horde/login.php to login to Horde (IMP) webmail.
The sentex_username is the first part of your email address.
(eg. sentex_username for would be just bitbucket)
Once logged into Horde, point your cursor to Mail at the top left and select Filters
Next, you will want to click on Spam Filter to enter the management area.
In here, you will be able to adjust the spam level and which folder will receive spam messages. By default, the spam level is 5 and the lower the number, the more aggressive the filtering will be.
Once you have modified the settings accordingly, click the 'Save and Enable' button.