use the sharpsvn. The specific revision logmessage want to change.
It is implemented like '[show log] -[edit logmessage]' of svn.
I am awkward in English. so, to help you understand. my code is attached.
public void logEdit()
{
Collection<SvnLogEventArgs> logitems = new Collection<SvnLogEventArgs>();
SvnRevisionRange range = new SvnRevisionRange(277, 277);
SvnLogArgs arg = new SvnLogArgs( range ) ;
m_svn.GetLog(new System.Uri(m_targetPath), arg, out logitems);
SvnLogEventArgs logs;
foreach (var logentry in logitems)
{
string autor = logentry.LogMessage; // only read ..
// autor += "AA";
}
// m_svn.Log( new System.Uri(m_targetPath), new System.EventHandler<SvnLogEventArgs> ());
}