Well it is the same issue as the one that I worked on, and unfortunately at the moment there is no cure. You see when the Outlook Addin makes a call to a URL, it passes the parameter to the WinAPI function call saying "use IE defaults", this means that the PAC file will get used. In testing we've done with Microsoft, Outlook doesn't do it's calls like that.
I can send you a PM with the Etrack reference number in it, and I can add your customer details to the Etrack, if you like? [Just let me know in reply to the PM]. At the moment though there are many higher priority defects in front of this, so it's not got a fix timeframe at all yet.
Working for cloudficient.com