Cannot shrink (seeming) emtpty tablespace

Hello all

            I have a tablespace in which I
            don't find any extents:

SQL> select segment_name from dba_extents where tablespace_name='BOVWALLS001';

no rows selected

            But I can't shrink the
            tablespace:

SQL> alter database datafile '/fs1/IMSMARE/tbsp/BOVWALLS001_0.tsf' resize 10M; alter database datafile '/fs1/IMSMARE/tbsp/BOVWALLS001_0.tsf' resize 10M
*

ERROR at line 1:
ORA-03297: file contains used data beyond requested RESIZE value

            Coalescing doesn't help,
            either (Though I'm not sure, if
            it should)

SQL> alter tablespace bovwalls001 coalesce;

Tablespace altered.

SQL> alter database datafile '/fs1/IMSMARE/tbsp/BOVWALLS001_0.tsf' resize 10M; alter database datafile '/fs1/IMSMARE/tbsp/BOVWALLS001_0.tsf' resize 10M
*

ERROR at line 1:
ORA-03297: file contains used data beyond requested RESIZE value

              
             Querying uet$:

SQL> select ext#, block#, length from uet$ where ts#=4 order by block#;

      EXT# BLOCK# LENGTH
---------- ---------- ----------

         0       1102         20
         0       1962         20
         0       2042         20
         0       6837         20
         0       8917         20
         0       9277         20
         0       9457         20
         0       9577         20
         0       9597         20

9 rows selected.

               Ok, there seems to be something
               in the tablespace (ts# = 4 is bovwalls001).

               But what is it and how do I get rid of it?




               MK