Fun with e-mail ports

I just set up a new domain e-mail address with an independent web hosting company. I successfully set up SSL using port 995 (POP3) and port 465 (SMTP) as recommended by the hosting company. This works fine when I am connected via my home Shaw account in Coquitlam. However, when I take my laptop to work (Burnaby) and connected via their Shaw Business account, my e-mail client (Outlook) fails to connect on port 995. There is no port screening (that I know of) set up at work (its a home office with residential router). Does Shaw selectively block (or use) port 995 for something (such as VOIP) in Burnaby?