title: How do I use a start commit hook in TortoiseSVN to setup a custom log entry?
body: <p>I'd like to automate TortoiseSVN as part of a commit process.
  Specifically I'd like to dynamically create a log entry for the commit dialog.</p>
  
  <p>I know that I can launch the commit dialog either from the commandline or by right clicking on a folder and selecting svncommit.</p>
  
  <p>I'd like to use the start commit hook to setup a log entry.
  I thought this worked by passing an entry file name in the MESSAGEFILE variable but when I add a hook script it cannot see this variable (hook launched successfully after right clicking and choosing svncommit).</p>
  
  <p>When I try using the commandline I use the /logmsgfile parameter but it seems to have no effect.</p>
  
  <p>I'm using tortoisesvn 1.5.3.</p>