The setup is the same than for your phone(refer to The HTC Dream page )
Open a new shell and do:
cd ~/replicant-2.2 ../bin/repo sync source build/envsetup.sh export ANDROID_JAVA_HOME=$JAVA_HOME make -j$(echo "$(grep 'processor' /proc/cpuinfo | wc -l ) + 1" | bc) sdk #uses arguments like -j9 to speed up build in case of multi-core cpu