[TYPO3] flexform description

[Stano Paška]

Hi.

Is there some documentation about flexform validation?
I found some examples of plugin parameters definition like:
<T3DataStructure>
<meta><langDisable>1</langDisable></meta>
<ROOT>
	<type>array</type>
	<el>
		<xmlTitle>
			<TCEforms>
				<label>Number of rows:</label>
				<config>
					<type>input</type>
					<size>48</size>
				</config>
			</TCEforms>
		</xmlTitle>
	</el>
</ROOT>
</T3DataStructure>

but I need check if BE user enters integer value.

There is some mention in typo3 core api, typo3.pdf, wiki "Extension Development, using Flexforms"
there are only simple examples.

Is there some complete DTD for T3DataStructure xml?

Thanks.

Stano.