Embed iframe gadjet height problem


Hi to all and Happy XMas

i want to embed the live gatzet…
The code that piwik gives me is something like

<div id="widgetIframe"><iframe width="100%" height="350" src="http://dap.ntua.gr/el/apps/piwik/index.php?module=Widgetize&action=iframe&moduleToWidgetize=Live&actionToWidgetize=widget&idSite=1&period=day&date=today&disableLink=1&widget=1" scrolling="no" frameborder="0" marginheight="0" marginwidth="0"></iframe></div>

Well the height of this iframe is bigger than 350px, but it’s not standar (it’s fixed)
What i must do to have a fixed height into iframe?