When you want to annotate PDFs using Ubuntu linux you've got the following possibilities:
- PDFXChange under WINE product page PDF XChange Viewer
- xournal user manual wikipedia entry
- evince - not yet having the needed capabilities (but they are planned for the future)
install PDFXChange
cd ~/Downloads; wget http://www.docu-track.com/PDFX_Vwr_Port.zip; unzip PDFX_Vwr_Port.zip
use PDFXChange:
wine ~/Downloads/PDFV_Portable/PDFXCview.exe