Document Classes ⇒ Beamer: Footnote in single slide

[schremmer]

(1) I have:

\begin{frame}
Some preliminary text.
\begin{enumerate}
\item
Text in first item
\item
Text in second item\footnote{just for the second item}
\end{enumerate}
\end{frame}

(2) In order to uncover the items in a step-wise fashion, I use
\beamerdefaultoverlayspecification{<+->}

(3) The footnote appears with the first item whereas I would like it to appear only when the second item is uncovered.

Looked in the user guide p. 130 and, more generally, a bit around but no luck.

Hopeful regards
--schremmer