[Tex/LaTex] Package xcolor warning when using sciposter document class

Question

Is there anyway to avoid the warning message

"Package xcolor Warning: Incompatible color definition on input line"
when using the Sciposter document class?

MWE:

\documentclass{sciposter}
\usepackage{lipsum}
\usepackage{epsfig}
\usepackage{amsmath}
\usepackage{amsthm}
\usepackage{amssymb}
\usepackage{mathrsfs}
\usepackage{multicol}
\usepackage{graphicx,url}
%\usepackage[french]{babel}   
\usepackage[utf8]{inputenc}
%\usepackage{fancybullets}
%=================LaTeXDraw==========
\usepackage{wrapfig}
\usepackage[usenames,dvipsnames]{pstricks}
\usepackage{epsfig}
\usepackage{pst-grad} % For gradients
\usepackage{pst-plot} % For axes
\usepackage{pst-3dplot}
\usepackage{pst-solides3d}
\begin{document}
%%% Begin of Multicols-Enviroment
\begin{multicols}{2}



%%% Introduction
\section{Introduction}


\begin{figure}
\psscalebox{1.0 1.0} % Change this value to rescale the drawing.
{
\begin{pspicture}(0,-3.3945527)(15.001626,3.3945527)
\psbezier[linecolor=black, linewidth=0.04](0.74162596,2.046916)(1.4787802,2.7226408)(4.3095756,3.4016163)(5.141626,2.846916)(5.973676,2.2922158)(8.199288,-1.786849)(7.941626,-2.753084)(7.6839633,-3.7193189)(4.529389,-3.3090465)(3.541626,-3.153084)(2.553863,-2.9971213)(0.8157258,-2.4335551)(0.341626,-1.5530839)(-0.13247384,-0.67261285)(0.004471836,1.3711914)(0.74162596,2.046916)
\end{pspicture}
}
\end{figure}

\end{multicols}
\end{document}

Answer 1

Use

\RequirePackage{xcolor}
\documentclass{sciposter}
\usepackage{lipsum}
[ ... ]