Borderlayout components are not visible within Tab content.

<tabbox width="100%">
		<tabs>
			<tab label="Inbox" />
		</tabs>
		<tabpanels>
			<tabpanel >
				<borderlayout height="100%">
					<north title="North" maxsize="300" size="50%"
						splittable="true" collapsible="true">
						<borderlayout>
							<west title="West" size="25%" flex="true"
								maxsize="250" splittable="true" collapsible="true">
								<div style="background:#B8D335">
									<label value="25%"
										style="color:white;font-size:50px" />
								</div>
							</west>
							<center border="none" flex="true">
								<div style="background:#E6D92C">
									<label value="25%"
										style="color:white;font-size:50px" />
								</div>
							</center>
							<east size="50%" border="none"
								flex="true">
								<label value="Here is a non-border"
									style="color:gray;font-size:30px" />
							</east>
						</borderlayout>
					</north>
				</borderlayout>
			</tabpanel>
		</tabpanels>
	</tabbox>

<borderlayout height="100%">

<borderlayout height="400px">