Export crashes everytime but unpredictable

Hello people,

First of, great tool. It worked the first time and was the only solution to get 
a backup.

Now, I have a problem. It worked the first time so I know it can be successful. 
I always open the app using CMD like so:

C:\Users\Hugo\Dorpje\BackUp google site>java -jar 
google-sites-liberation-1.0.3.jar

Then it starts to run. I enter the correct details and it starts to export 
well. But after some downloads the app just freezes and at that time the CMD 
window shows the following:

Exception in thread "Thread-4" java.lang.NullPointerException: text
        at com.google.common.base.Preconditions.checkNotNull(Preconditions.java:
203)
        at com.google.sites.liberation.renderers.RendererUtils.getHyperLink(Rend
ererUtils.java:141)
        at com.google.sites.liberation.renderers.RendererUtils.getAuthorElement(
RendererUtils.java:72)
        at com.google.sites.liberation.renderers.CommentsRendererImpl.renderComm
ents(CommentsRendererImpl.java:40)
        at com.google.sites.liberation.export.PageExporterImpl.exportPage(PageEx
porterImpl.java:181)
        at com.google.sites.liberation.export.SiteExporterImpl.exportPage(SiteEx
porterImpl.java:158)
        at com.google.sites.liberation.export.SiteExporterImpl.exportSite(SiteEx
porterImpl.java:131)
        at com.google.sites.liberation.util.GuiMain$ImportExportRunnable.run(Gui
Main.java:279)
        at java.lang.Thread.run(Unknown Source)

It is like this every time I try. The app downloads the pages in random order 
and stops at a random page, also pages with very little content. I use the 
1.0.3 version and am running Windows 7.

I have no experience with Java so the problem is a total blur to me. Can anyone 
please help me?

Original issue reported on code.google.com by pousch...@hotmail.com on 8 Nov 2010 at 10:11

eservent / google-sites-liberation

Export crashes everytime but unpredictable #66