Cannot build on Debian: no fontconfig and unmet dependencies

Hello,

I have been trying to build LibreOffice on Debian Squeeze using the 
instructions at
http://wiki.documentfoundation.org/Development/Native_Build

I ran ./autogen.sh, but I currently am getting the following error:

checking for FONTCONFIG... no
configure: error: Package requirements (fontconfig >= 2.2.0) were not met:

No package 'fontconfig' found

Consider adjusting the PKG_CONFIG_PATH environment variable if you
installed software in a non-standard prefix.

Alternatively, you may set the environment variables FONTCONFIG_CFLAGS
and FONTCONFIG_LIBS to avoid the need to call pkg-config.
See the pkg-config man page for more details.
Error running configure at ./autogen.sh line 157.



I followed the advice that I found on Google and did the following:

$ apt-get build-dep libreoffice
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to find a source package for libreoffice

$ apt-get build-dep openoffice.org
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages have unmet dependencies:
 libcairo2-dev : Depends: libpixman-1-dev (>= 0.18.4) but it is not 
going to be installed
 xulrunner-dev : Depends: libnss3-dev but it is not going to be installed
E: Build-dependencies for openoffice.org could not be satisfied.

What should I do in this situation? Any help appreciated.

Andrew.