Future post strange behavior

My future post function at linux fedora 5 has a strange behavior.
For example:
1. At 1st April 2007 13:40, post a future post, titled “test” time stamp is set to 1st April 2007 13:50
2. At 13:45, Dashboard->Scheduled Entries apper a “test in 5 mins”, seems OK.
3. At 13:49, Dashboard->Scheduled Entries apper a “test in 1 mins”, seems OK.
4. At 13:50, this post doesn’t appear in my blog, future post doesn’t work.
5. At 13:51, Dashboard->Scheduled Entries apper “test in 1 mins.
5. At 13:55, Dashboard->Scheduled Entries apper “test in 5 mins.
6. At 2nd April 2007 13;50, Dashboard->Scheduled Entries apper “test in 1 day”