User:AaronPeterson/kdesettingsFixes
From websvn, the icon plasmoid, this suggests a method to fix it.
Plasma::ToolTipManager::self()->unregisterWidget(m_icon);
250 m_icon->setDrawBackground(true);
251 } else {
252 //in the panel the icon behaves like a button
253 connect(m_icon, SIGNAL(clicked()), this, SLOT(openUrl()));
254 m_icon->setText(QString());
255 Plasma::ToolTipContent data(m_text, m_genericName, m_icon->icon());
256 Plasma::ToolTipManager::self()->setContent(m_icon, data);
257 m_icon->setDrawBackground(false);