Is port # required for web service url?

Currently, we are using a web service URL without a port #; however, once I use that url and login the next time to analysis for office... it adds port 80.

For example, the web service url we use is: http://bobj.company.com/dswsbobje/services/Session

And the web service url that is saved and stored the next time I attempt to login is: http://bobj.company.com:80/dswsbobje/services/Session

Is port # required? I was told that with load balancing, no port # is necessary...

Thanks!

Using Analysis for Office v. 1.4.2.2625