Images in pdflatex frontpage
 

Hi all,
I'm writing a thesis in Latex, and must put the university's logo in the front page, up the document title. For various reason I decided to use the book class, and I'm using pdflatex with the hyperref packge. Now, if I try to add the logo image, i got an error like these:

------ERROR--------

loading : Context Support Macros / PDF
) <logo.jpg, id=203, 105.39375pt x 104.39pt> <use logo.jpg> [1{/usr/share/texmf
/dvips/config/pdftex.map} <./logo.jpg>] [2]
! pdfTeX warning (ext4): destination with the same identifier (name{page.i}) ha
s been already used, duplicate ignored
<to be read again>
\penalty
l.21
[1]
! pdfTeX warning (ext4): destination with the same identifier (name{page.ii}) h
as been already used, duplicate ignored
<to be read again>
\penalty

---------ERROR--------------

which seems to be connected with the page numbering. The errors disappear as soon as I remove the \includegraphics command. I tried to remove the \maketitle command, and write the title on my own: it worked, but now the frontpage gets numbered, and that's not nice.
Here is the sensitive part of the document:

\usepackage[backref=page,plainpages=false,pdfpagelabels]{hyperref}
% This is for page numbering

\usepackage[pdftex]{color,graphicx}

\begin{document}

\frontmatter
\includegraphics{logo.jpg}
\maketitle

\chapter{Preface}
[...]
\mainmatter
[...]

\backmatter
[...]
\appendix
[...]

---------------------------

Hope someone can help
thx
Giovanni