>> You're seriously telling me that corporate networks don't allow Citrix ICA traffic through - as a matter of policy? <<
Here is the deal. I contracted at a place that sent sales leads to hundreds of businesses. They used VB with Cytrix. Enough of those 100+ "consumers" of the data complained that either their firewall would not let the information through, or they did not have the staff to troubleshoot/change/approve the firewall problems. (Some customers were big and some were small.)
It was a big enough complaint that the data distributor (the place I contracted at) decided to make a web-based version using Java. (Coordinating Java certs was a major pain, and was not yet fully solved by that developer when my stint was up. They used Java because they wanted a decent grid and HTML didn't give it. But that is another story. Personally IMO they didn't think it through enough.)
The customer is always right and enuf customers complained about Cytrix and the firewalls.