I cannot remember when I installed these two Like/Dislike modules. However since at least WordPress version 2.8.3 these plugins break the posting process of new posts. The content either remains empty for new posts or unchanged for existing posts.

Consequently I had to temporary deactivate the plugins:

• Visitor Like/Dislike Comment Rating version 1.0.5
• Visitor Like/Dislike Post Rating version 1.5.8