Paging not working when searching and sorting by created on

Hi,

We've found an odd bug in CRM 2011 and I'm not sure where to look in order to fix this. Have you faced the same issue?

When doing a search (advanced find or main grid) and sorting the result by the Created On column, if there are more then 250 results and paging is applied, when click to next page, the page number changes but the results don't, when click again the results number increase, but the records in the screen don't change, only shows the first page.. 

Any thoughts? 

Thanks