Problem with identical sequence names if do export in MSF format

1. Open COI.aln
2. Give the first three sequences the same name "test"
3. Export->Save sibaligment
4. Select these three sequences in "Extract Selected as MSA" dialog
5. Select "File format to use"=MSF
6. Push Extract button
Expected state: Different names for these sequences
Actual state: COI.subalign.msf file is opened with the same names: "test", "test" and "test"

7. Close COI.subalign.msf and open it again
Actual state: 3 different names: "test", "test_1" and "test_2"