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[FIXED] GXT 2.1 - Portlet Constructor Bug
Using the layout constructor (public Portlet(Layout layout)) does not add style name "x-portlet".
The most noticeable effect is that there are no top or bottom margins for the portlet.
Use the default constructor and then set the layout using the setLayout method.
This bug is fixed in the releases/2.1 branch and is now available in the 2.1.1-beta release available here.