I replaced the code for loop with the following. Now it works for MS SQL2k...

        for (;!$t_result->EOF;) {
            # hide private bugs if user doesn't have access to view them.
            $t_row = db_fetch_array( $t_result );

            if ( !$t_can_view_private && ( $t_row['view_state'] == VS_PRIVATE ) ) {
                continue;
            }

            # check limit_Reporter (Issue #4770)
            # reporters can view just issues they reported
            if ( ON === $t_limit_reporters && $t_user_access_level_is_reporter &&
                 !bug_is_user_reporter( $t_row['id'], $t_user_id )) {
              continue;
            }

            $t_issue_id = $t_row['id'];

            if ( !helper_call_custom_function( 'changelog_include_issue', array( $t_issue_id ) ) ) {
                continue;
            }

            # Print the header for the version with the first changelog entry to be added.
            if ( $t_first_entry && !$t_version_header_printed ) {
                if ( $i > 0 ) {
                    echo '<br />';
                }

                print_version_header( $t_version_id );

                $t_version_header_printed = true;
                $t_first_entry = false;
            }

            helper_call_custom_function( 'changelog_print_issue', array( $t_issue_id ) );
        }

With Oracle I had the same problem, this is the solution :

for ( $t_result = db_query( $query ); !$t_result->EOF; $t_result->MoveNext() ) {

hide private bugs if user doesn't have access to view them.

            if ( !$t_can_view_private && ( $t_result->fields['view_state'] == VS_PRIVATE ) ) {
                continue;
            }
            # check limit_Reporter (Issue #4770)
            # reporters can view just issues they reported
            if ( ON === $t_limit_reporters && $t_user_access_level_is_reporter &&
                 !bug_is_user_reporter( $t_result->fields['id'], $t_user_id )) {
              continue;
            }
            //$t_issue_id = $t_result->fields['id'];
            //MODIFICATION probleme de valeur ID vide BUG non trouve
            //SOLUTION------------------------------
            $row=db_fetch_array($t_result);
            $t_issue_id =$row['id'];
        //---------------------------------------

            if ( !helper_call_custom_function( 'changelog_include_issue', array( $t_issue_id ) ) ) {
                continue;
            }

            # Print the header for the version with the first changelog entry to be added.
            if ( $t_first_entry && !$t_version_header_printed ) {
                if ( $i > 0 ) {
                    echo '<br />';
                }

                print_version_header( $t_version_id );

                $t_version_header_printed = true;
                $t_first_entry = false;
            }

            helper_call_custom_function( 'changelog_print_issue', array( $t_issue_id ) );
        }

This is fixed as part 0006888. I didn't mark this as duplicate and set the category to "db oracle" so that the changelog reflects that it is fixed for both MS SQL and Oracle. The fix will be included in Mantis 1.1 and is available in CVS.

MantisBT currently supports Mysql and has support for other database engines.

The support for other databases is known to be problematic.

Having implemented the current database layer into Mantis 10 years ago, I'm currently working on replacing the current layer.

If you are interested in using Mantis with non-mysql databases - for example, Oracle, PGSQL or MSSQL, and would be willing to help out testing the new database layer, please drop me an email at paul@mantisforge.org

In the meantime, I'd advise running Mantis with Mysql Only to avoid issues.

Thanks
Paul