Why when I add package paralist into my beamer presentation, enumerate stops working?

Question

I try to simple use beamer with enumerate and compactenum from paralist. But when I add paralist package in document, enumerate just stops working.

\documentclass{beamer}
\usepackage{paralist}
\usepackage{pifont}

\begin{document}
\begin{frame}
\frametitle{...}
\begin{compactenum}[{\ding{79}}]
\item ...
\item ,,,
\item  ...
\end{compactenum}

\begin{enumerate}
\item 1
\item 2
\item 3
\end{enumerate}
\end{frame}
\end{document}

The control sequence at the end of the top line of your error message was never \def'ed. If you have misspelled it (e.g., \hobx'), typeI' and the correct spelling (e.g., `I\hbox'). Otherwise just continue, and I'll forget about whatever was undefined.

When I do not use paralist (and do not use compactenum) than the process will end normally. I know beamer defines many things and adding paralist can make conflicts in definitions but I do not know how to fix it.

Answer 1

The answer is: "because that packages overwrite beamer configuration" (as Ulrike Fischer said).

P.S.: At the end I use following "solution":

\documentclass{beamer}
\usepackage{paralist}
\usepackage{pifont}
\setdefaultenum{1)}{a.}{i)}{A}

\begin{document}      
\begin{frame}
\frametitle{"enumerate"}
\begin{compactenum}
\item 1
\item 2
\item 3
\end{compactenum}
\end{frame}

\begin{frame}
\frametitle{"itemize"}
\begin{compactenum}[{\ding{81}}]
\item *    
\item *
\end{compactenum}
\end{frame}  
\end{document}  

But surely it will be more clear to listen to Ulrike Fischer: "Use the commands of beamer to configure your lists do not load packages which redefines lists in beamer."