Maybe I don't understand, but AFAIK you need to specify different context roots to differentiate your two apps.
If you really [b]must[/b] have [b]one[/b] physical server but [b]two[/b] virtual hosts each serving a [different] default web app, then you need to configure virtual hosts and map them to the target context roots. I think you can do this in GF but virtual hosts is the key (again, AFAIK).
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