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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.
Sencha - GXT Dev Team
This bug is fixed in the releases/2.1 branch and is now available in the 2.1.1-beta release available here.