svn - How to do subversion merge cherry picking without conflicts -

using svn 1.8, cannot figure out what's best way reintegrate merge cherrypicking (i.e. don't want merge revisions trunk). goes smooth long merge revisions, like:

svn merge ^/branches/mybranch 

now have 1 revision in branch shouldn't merged trunk, let's svn 'history' this:

rev 20: reintegrated branch => trunk rev 21: added 'donotmergetotrunk.txt' branch 'mybranch' rev 22: added 'monkey.txt' trunk rev 23: added 'dog.txt' branch 'mybranch' rev 24: merged trunk => mybranch, monkey.txt added branch 

now want reintegrate revision 21 mybranch trunk, whatever try, keep getting conflict

tree conflict on 'monkey.txt'     local file obstruction, incoming file add upon merge 

i have tried stuff like:

svn merge -r 21:24 ^/branches/mybranch svn merge -r 1:20 -r 21:24 ^/branches/mybranch 

of course conflict can solved manually, in real life many conflicts way , solving them gets quite tedious.

how perform merge without getting conflicts?

in easy case have merge -r 23:24

in more common case can use smallest needed range in src in form -rn:m , exclude unwanted revisions inside range using reverse merge of changesets: -c -r