svn merge fails "Out of memory - terminating application." or Tortoise runtime error

Am I doing something wrong? Should I break my merge up into chunks?

I am trying to merge some changes from one branch to another. The two
branches are currently unrelated. When I try I get the following:

  Out of memory - terminating application.

  This application has requested the Runtime to terminate it in an unusual
way.
  Please contact the application's support team for more information.

svn log -v gives me about 1890 lines of data for the action. so, it doesn't
seem like much work. Please let me know if this is a known issue. Thanks.

-- 
Peter Kahn
citizenkahn_at_gmail.com
pkahnpie1_at_AIM
http://citizenkahn.myplaxo.com
Awareness - Intention - Action