How to maintain clean history in main branch?

[Bela Babik]

>  However, merge doesn't work:
>  abort: can't merge with ancestor

Works for me with a named branch:

$ hg slog

o  3[tip] |sa| ee5a8bd21e94   2008-04-24 16:36 +1000   user
|    mt
|
@  2  6f7f2d880544   2008-01-09 16:52 +1100   user
|    m.c added
|
o  1  82e55d328c8c   2005-08-26 01:21 -0700   mpm
|    Create a makefile
|
o  0  0a04b987be5a   2005-08-26 01:20 -0700   mpm
     Create a standard "hello, world" program


$ hg merge sa

1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)

$ hg commit -m 'bm'

$ hg slog

@    4[tip]:2,3  1a3b087c4587   2008-04-24 16:37 +1000   user
|\     bm
| |
| o  3 |sa| ee5a8bd21e94   2008-04-24 16:36 +1000   user
|/     mt
|
o  2  6f7f2d880544   2008-01-09 16:52 +1100   user
|    m.c added
|
o  1  82e55d328c8c   2005-08-26 01:21 -0700   mpm
|    Create a makefile
|
o  0  0a04b987be5a   2005-08-26 01:20 -0700   mpm
     Create a standard "hello, world" program