On RSS page not complete information is shown in Opera

Steps to reproduce:
1. Login jcommune with user which have permission to create posts.
2. Go to the topic and create a post.
3. Open RSS page in Opera.
AR: the content of post is not shown on RSS page (only topic title, date and author) .
ER: complete information about new post is shown on RSS page (topic title, date, author, post content).