This is design intent. The reporter sets the severity of the problem. Only those who can handle the issue (e.g., the design team) can set the priority.

ok.
In this case there should be in my opinion a better possibility for the manager to edit the priority. Under "Viewing Issue Simple Details" there is an easy way to assign the issue and to change the priority. I would really appreciate an equal field/button to change the priority of the issue.
At the moment I use the "view_all_bug_page.php", check the issues and click then "Update Priority" from the dropdown-box at the end of the page.

You can also do this on an individual basis by clicking "Update Issue". This allows you to edit any field in the issue.

Thank you for taking the time to report a problem with mantis.

Since this problem report was originally made, a number of releases have occured. Additionally no recent feedback has been received on this issue.
It appears that this issue has either been fixed, or may not be a relevant report for the current release.

Unfortunately you are not using the latest version and the problem might already be fixed. Please download the latest release from http://www.mantisbt.org/download.php [^] [^]

If you are able to reproduce this bug in the current release, or have some more information on how this feature could be improved in the current release. Please either change the mantis version on this bug report
to the version you tested and change the status back to "Open", or open a new issue report with more information.

Again, thank you for your continued support and report.